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Main focus is epidemiology of sleep and psychiatric disorders in the general population and clinical settings: 1)sleep habits and patterns; 2) prevalence, diagnosis, co-morbidity, treatment and Public Health impact of sleep disorders; 3) pain, posttraumatic stress disorder, social phobia, panic disorder and generalized anxiety; 4) epidemiology of narcolepsy and hypersomnia.

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Abstract

Our study aims to explore the associations between outdoor nighttime lights (ONL) and sleep patterns in the human population.Cross-sectional telephone study of a representative sample of the general US population age 18 y or older. 19,136 noninstitutionalized individuals (participation rate: 83.2%) were interviewed by telephone. The Sleep-EVAL expert system administered questions on life and sleeping habits; health; sleep, mental and organic disorders (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision; International Classification of Sleep Disorders, Second Edition; International Classification of Diseases, 10(th) Edition). Individuals were geolocated by longitude and latitude. Outdoor nighttime light measurements were obtained from the Defense Meteorological Satellite Program's Operational Linescan System (DMSP/OLS), with nighttime passes taking place between 19:30 and 22:30 local time. Light data were correlated precisely to the geolocation of each participant of the general population sample.Living in areas with greater ONL was associated with delayed bedtime (P < 0.0001) and wake up time (P < 0.0001), shorter sleep duration (P < 0.01), and increased daytime sleepiness (P < 0.0001). Living in areas with greater ONL also increased the dissatisfaction with sleep quantity and quality (P < 0.0001) and the likelihood of having a diagnostic profile congruent with a circadian rhythm disorder (P < 0.0001).Although they improve the overall safety of people and traffic, nighttime lights in our streets and cities are clearly linked with modifications in human sleep behaviors and also impinge on the daytime functioning of individuals living in areas with greater ONL.

Abstract

Excessive sleepiness or hypersomnolence is currently defined by two main symptoms: 1) the excessive amount of sleep, defined as a prolonged period of main sleep or the presence of naps; and 2) poor quality of awakening. Excessive sleepiness was reported by 27.8%. The presence of recurrent periods of irresistible sleep in the same day was found in 13.2%, recurrent naps in the same day in 1.9%, non-restorative sleep despite a nighttime sleep of more than 9 hours (0.7%), as well as a sleep drunkenness (4.4%). Adding criteria for duration and frequency (minimum of 3 times per week and duration of at least 3 months), having social or professional impairment and psychological distress, and after excluding significant associated comorbidities, the prevalence fall to 1.5%. These very important prevalence hypersomnolence figures constitute an excellent argument to educate doctors and health authorities on the need to identify and support the excessive sleepiness disorders.

Abstract

In this study, we used a strict definition of hypersomnia and tested if the association between overeating-hypersomnia remained positive and significant. Hypersomnia was present if the total sleep time was close to 10h per day or was at least 2h longer than in normothymic periods.Cross-sectional study using the adult general population of California and New York. The sample was composed of 6694 individuals aged between 18 and 96years. Participants were interviewed by telephone using the Sleep-EVAL system. The interviews included various sleep and health topics and the assessment of DSM-IV sleep and psychiatric disorders.The one-month prevalence of major depressive episode was 6.1%, including a one-month prevalence of atypical depression of 1.6%, in this sample. Atypical depression subjects had a greater number of depressive symptoms and a longer duration of the current depressive episode than the other depressive subjects. Depressive subjects with hypersomnia slept longer (8h, 29min) than the other depressive subjects (6h, 36min) and longer than the subjects "getting too much sleep" (6h, 48min). Furthermore, hypersomnia was not associated with overeating while "getting too much sleep" showed a positive association with overeating.Hypersomnia needs to be evaluated using a strict definition. Otherwise, it leads to an overestimation of this symptom in major depressive episode subjects and to a false association with overeating.

Abstract

The objective of this study was to determine the extent that confusional arousals (CAs) are associated with mental disorders and psychotropic medications.Cross-sectional study conducted with a representative sample of 19,136 noninstitutionalized individuals of the US general population aged 18 years or older. The study was performed using the Sleep-EVAL expert system and investigated sleeping habits; health; and sleep, mental, and medical conditions (DSM-IV-TR, ICSD-II, ICD-10).A total of 15.2% (95% confidence interval 14.6%-15.8%) (n = 2,421) of the sample reported episodes of CAs in the previous year; 8.6% had complete or partial amnesia of the episodes and 14.8% had CAs and nocturnal wandering episodes. Eighty-four percent of CAs were associated with sleep/mental disorders or psychotropic drugs. Sleep disorders were present for 70.8% of CAs. Individuals with a circadian rhythm sleep disorder or a long sleep duration (?9 hours) were at higher risk of CAs. Mental disorders were observed in 37.4% of CAs. The highest odds were observed in individuals with bipolar disorders or panic disorder. Use of psychotropic medication was reported by 31.3% of CAs: mainly antidepressant medications. After eliminating possible causes and associated conditions, only 0.9% of the sample had CA disorder.CAs are highly prevalent in the general population. They are often reported allegedly as a consequence of the treatment of sleep disorders. For the majority of subjects experiencing CAs, no medications were used, but among those who were using medications, antidepressants were most common. Sleep and/or mental disorders were important factors for CAs independent of the use of any medication.

Chronic Obstructive Pulmonary Disease and its association with sleep and mental disorders in the general populationJOURNAL OF PSYCHIATRIC RESEARCHOhayon, M. M.2014; 54: 79-84

Abstract

To assess the prevalence of insomnia symptoms in Chronic Obstructive Pulmonary Disease (COPD) participants, their association with psychiatric disorders and their impact on health care utilization and quality of life.It is a cross-sectional telephone study using a representative sample consisting of 10,854 non-institutionalized individuals aged 15 or over living in Germany, Spain and the United Kingdom. Interviews were managed by the Sleep-EVAL expert system. The questionnaire included questions on sleeping habits, life habits, health, DSM-IV mental disorders, DSM-IV and ICSD sleep disorders. COPD was defined as chronic bronchitis or emphysema (treated or not) diagnosed by a physician.A total of 2.5% [2.1%-2.8%] of the sample reported having been diagnosed with COPD. As many as 48.1% of COPD had insomnia symptoms, which was twice higher than the rate observed in non-COPD (OR: 2.4). Only 11.8% of COPD addressed their sleep difficulties to their physician. Mental disorders were higher in COPD compared to non-COPD participants: Major Depressive disorder (AOR: 2.8); Generalized Anxiety Disorder (AOR: 11.0); Panic Disorder (AOR: 7.1) and Specific Phobia (AOR: 3.7). As many as 84.4% of COPD with depression and 59.7% of those with an Anxiety Disorder had associated insomnia symptoms. The co-occurrence of both conditions increased by five times the likelihood of hospitalizations in the previous year among COPD. Both conditions were associated with a diminished Quality of Life in COPD.COPD is a debilitating disease accompanied with psychiatric disorders and sleep disturbances in the overwhelming majority of cases. This high comorbidity is associated with greater health care utilization and great deterioration of the quality of life.

Abstract

The link between sleepiness and the risk of motor vehicle accidents is well known, but little is understood regarding the risk of home, work and car accidents of subjects with insomnia. An international cross-sectional survey was conducted across 10 countries in a population of subjects with sleep disturbances. Primary care physicians administered a questionnaire that included assessment of sociodemographic characteristics, sleep disturbance and accidents (motor vehicle, work and home) related to sleep problems to each subject. Insomnia was defined using the International Classification of Sleep Disorders (ICSD-10) criteria. A total of 5293 subjects were included in the study, of whom 20.9% reported having had at least one home accident within the past 12 months, 10.1% at least one work accident, 9% reported having fallen asleep while driving at least once and 4.1% reported having had at least one car accident related to their sleepiness. All types of accident were reported more commonly by subjects living in urban compared to other residential areas. Car accidents were reported more commonly by employed subjects, whereas home injuries were reported more frequently by the unemployed. Car accidents were reported more frequently by males than by females, whereas home accidents were reported more commonly by females. Patients with insomnia have high rates of home accidents, car accidents and work accidents related to sleep disturbances independently of any adverse effects of hypnotic treatments. Reduced total sleep time may be one factor explaining the high risk of accidents in individuals who complain of insomnia.

Abstract

To evaluate the mortality rate in patients with narcolepsy.Data were derived from a large database representative of the US population, which contains anonymized patient-linked longitudinal claims for 173 million individuals.Symphony Health Solutions (SHS) Source Lx, an anonymized longitudinal patient dataset.All records of patients registered in the SHS database between 2008 and 2010.None.Identification of patients with narcolepsy was based on ? 1 medical claim with the diagnosis of narcolepsy (ICD-9 347.xx) from 2002 to 2012. Dates of death were acquired from the Social Security Administration via a third party; the third party information was encrypted in the same manner as the claims data such that anonymity is ensured prior to receipt by SHS. Annual all-cause mortality rates for 2008, 2009, and 2010 were calculated retrospectively for patients with narcolepsy and patients without narcolepsy in the database, and standardized mortality ratios (SMR) were calculated. Mortality rates were also compared with the general US population (Centers for Disease Control data). SMRs of the narcolepsy population were consistent over the 3-year period and showed an approximate 1.5-fold excess mortality relative to those without narcolepsy. The narcolepsy population had consistently higher mortality rates relative to those without narcolepsy across all age groups, stratified by age decile, from 25-34 years to 75+ years of age. The SMR for females with narcolepsy was lower than for males with narcolepsy.Narcolepsy was associated with approximately 1.5-fold excess mortality relative to those without narcolepsy. While the cause of this increased mortality is unknown, these findings warrant further investigation.

Abstract

To examine how occupational activities (work, school), separation from parents, environmental conditions, stressors ad social insertion affect on the prevalence of Major Depressive Disorder (MDD) and mental health care-seeking among young adults.Cross-sectional study conducted in two samples: 1) 19,136 subjective representative of the US non-institutionalized general population including 2082 18-26 y.o. subjects. 2) 2196 subjects representative of the students' population living on an university campus. Telephone interviews were realized using the Sleep-EVAL system to assess sleeping habits, general health, organic, sleep and mental disorders.One-month prevalence of depressed mood was similar between community and campus student groups (21.7% and 23.4%), and less common than for working (23.6%) and non-working (28.2%) young adults in the community. One-month MDD was found in 12.0% of non-working young people, compared with 6.6% of young workers, 3.2% of on-campus students and 4.1% of students in the general population (p

Abstract

This study aims to examine the association between the chronotype (morningness/eveningness) and specific mental disorders.Cross-sectional epidemiological study conducted in three in-patient clinical settings. A total of 1468 consecutive in-patients who gave their written consent were enrolled. On the admission day, patients filled sleep questionnaires and a nurse filled a Clinical Global Impressions scale. Hospitalization reports and ICD-10 diagnoses were collected.Sleep/wake schedule was similar between the psychiatric diagnoses. On the other hand, morning type patients had an earlier bedtime, earlier wakeup time and shorter sleep duration than the other chronotype regardless of the diagnosis. In multivariate models, patients with a depressive disorder or a psychosis were more likely to be morning type. Patients with an anxiety disorder, addiction disorder or personality disorder were more likely to be evening type.Age and sleep/wake schedule are contributing factors for the chronotype but mental disorders too appeared to modulate chronotype preferences.

Abstract

Using population-based data, we document the comorbidities (medical, neurologic, and psychiatric) and consequences for daily functioning of excessive quantity of sleep (EQS), defined as a main sleep period or 24-hour sleep duration ?9 hours accompanied by complaints of impaired functioning or distress due to excessive sleep, and its links to excessive sleepiness.A cross-sectional telephone study using a representative sample of 19,136 noninstitutionalized individuals living in the United States, aged ?18 years (participation rate = 83.2%). The Sleep-EVAL expert system administered questions on life and sleeping habits; health; and sleep, mental, and organic disorders (Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revision; International Classification of Sleep Disorders: Diagnostic and Coding Manual II, International Classification of Diseases and Related Health Problems, 10th edition).Sleeping at least 9 hours per 24-hour period was reported by 8.4% (95% confidence interval = 8.0-8.8%) of participants; EQS (prolonged sleep episode with distress/impairment) was observed in 1.6% (1.4-1.8%) of the sample. The likelihood of EQS was 3 to 12× higher among individuals with a mood disorder. EQS individuals were 2 to 4× more likely to report poor quality of life than non-EQS individuals as well as interference with socioprofessional activities and relationships. Although between 33 and 66% of individuals with prolonged sleep perceived it as a major problem, only 6.3 to 27.5% of them reported having sought medical attention.EQS is widespread in the general population, co-occurring with a broad spectrum of sleep, medical, neurologic, and psychiatric disorders. Therefore, physicians must recognize EQS as a mixed clinical entity indicating careful assessment and specific treatment planning. ANN NEUROL 2013;73:785-794.

Narcolepsy is complicated by high medical and psychiatric comorbidities: a comparison with the general population.Sleep medicineOhayon, M. M.2013; 14 (6): 488-492

Abstract

Individuals affected with narcolepsy represent a vulnerable segment of the population. However, we only have a partial understanding of this vulnerability. Our study aims to examine psychiatric disorders and medical conditions associated with narcolepsy.A total of 320 narcoleptic participants were interviewed regarding sleeping habits, health, medication consumption, medical conditions (International Statistical Classification of Diseases and Related Health Problems, 10th edition), sleep disorders (International Classification of Sleep Disorders, second edition [ICSD-2]) and mental disorders (Diagnostic and Statistical Manual of Mental Disorders, fourth edition, text revision [DSM-IV-TR]) using Sleep-EVAL. A general population comparison sample (N=1464) matched for age, sex, and body mass index (BMI) and interviewed with the same instrument was used to estimate odds ratios (OR).Five diseases were more frequently observed among narcoleptic participants, including hypercholesterolemia (OR, 1.51), diseases of the digestive system (OR, 3.27), heart diseases (OR, 2.07), upper respiratory tract diseases (OR, 2.52), and hypertension (OR, 1.32). Most frequent psychiatric disorders among the narcolepsy group were major depressive disorder (MDD) (OR, 2.67) and social anxiety disorder (OR, 2.43), both affecting nearly 20% of narcoleptic individuals. However, most mood and anxiety disorders were more prevalent among the narcoleptic group. Alcohol abuse or alcohol dependence was comparable between groups.Narcolepsy is associated with a high comorbidity of both medical conditions and psychiatric disorders that need to be addressed when developing a treatment plan.

Abstract

The associations between depressive symptoms and hypersomnia are complex and often bidirectional. Of the many disorders associated with excessive sleepiness in the general population, the most frequent are mental health disorders, particularly depression. However, most mood disorder studies addressing hypersomnia have assessed daytime sleepiness using a single response, neglecting critical and clinically relevant information about symptom severity, duration and nighttime sleep quality. Only a few studies have used objective tools such as polysomnography to directly measure both daytime and nighttime sleep propensity in depression with normal mean sleep latency and sleep duration. Hypersomnia in mood disorders, rather than a medical condition per se, is more a subjective sleep complaint than an objective finding. Mood symptoms have also been frequently reported in hypersomnia disorders of central origin, especially in narcolepsy. Hypocretin deficiency could be a contributing factor in this condition. Further interventional studies are needed to explore whether management of sleep complaints improves mood symptoms in hypersomnia disorders and, conversely, whether management of mood complaints improves sleep symptoms in mood disorders.

Abstract

To examine the association of sleep complaints reported at baseline (insomnia complaints and excessive daytime sleepiness (EDS)) and medication, with cognitive decline in community-dwelling elderly.An 8-yr longitudinal study.The French Three-City Study.There were 4,894 patients without dementia recruited from 3 French cities and having a Mini-Mental Status Examination (MMSE) score ? 24 points at baseline.Questionnaires were used to evaluate insomnia complaints (poor sleep quality (SQ), difficulty in initiating sleep (DIS), difficulty in maintaining sleep (DMS), early morning awakening (EMA)), EDS, and sleep medication at baseline. Cognitive decline was defined as a 4-point reduction in MMSE score during follow-up at 2, 4, and 8 yr. Logistic regression models were adjusted for sociodemographic, behavioral, physical, and mental health variables, and apolipoprotein E genotype. EDS independently increased the risk of cognitive decline (odds ratio (OR) = 1.26, 95% confidence interval (CI) = 1.02-1.56), especially for those patients who also developed dementia during the follow-up period (OR = 1.39, 95% CI = 1.00-1.97). The number of insomnia complaints and DMS were negatively associated with MMSE cognitive decline (OR = 0.77, 95% CI = 0.60-0.98 for 3-4 complaints, OR = 0.81, 95% CI = 0.68-0.96, respectively). The 3 other components of insomnia (SQ, DIS, EMA) were not significantly associated with MMSE cognitive decline.Our results suggest that EDS may be associated independently with the risk of cognitive decline in the elderly population. Such results could have important public health implications because EDS may be an early marker and potentially reversible risk factor of cognitive decline and onset of dementia.

Abstract

Restless legs syndrome (RLS) has gained considerable attention in the recent years: nearly 50 community-based studies have been published in the last decade around the world. The development of strict diagnostic criteria in 1995 and their revision in 2003 helped to stimulate research interest on this syndrome. In community-based surveys, RLS has been studied as: 1) a symptom only, 2) a set of symptoms meeting minimal diagnostic criteria of the international restless legs syndrome study group (IRLSSG), 3) meeting minimal criteria accompanied with a specific frequency and/or severity, and 4) a differential diagnosis. In the first case, prevalence estimates in the general adult population ranged from 9.4% to 15%. In the second case, prevalence ranged from 3.9% to 14.3%. When frequency/severity is added, prevalence ranged from 2.2% to 7.9% and when differential diagnosis is applied prevalence estimates are between 1.9% and 4.6%. In all instances, RLS prevalence is higher in women than in men. It also increases with age in European and North American countries but not in Asian countries. Symptoms of anxiety and depression have been consistently associated with RLS. Overall, individuals with RLS have a poorer health than non-RLS but evidence for specific disease associations is mixed. Future epidemiological studies should focus on systematically adding frequency and severity in the definition of the syndrome in order to minimize the inclusion of cases mimicking RLS.

Abstract

To assess the prevalence and comorbid conditions of nocturnal wandering with abnormal state of consciousness (NW) in the American general population.Cross-sectional study conducted with a representative sample of 19,136 noninstitutionalized individuals of the U.S. general population ?18 years old. The Sleep-EVAL expert system administered questions on life and sleeping habits; health; and sleep, mental, and organic disorders (DSM-IV-TR; International Classification of Sleep Disorders, version 2; International Classification of Diseases-10).Lifetime prevalence of NW was 29.2% (95% confidence interval [CI] 28.5%-29.9%). In the previous year, NW was reported by 3.6% (3.3%-3.9%) of the sample: 1% had 2 or more episodes per month and 2.6% had between 1 and 12 episodes in the previous year. Family history of NW was reported by 30.5% of NW participants. Individuals with obstructive sleep apnea syndrome (odds ratio [OR] 3.9), circadian rhythm sleep disorder (OR 3.4), insomnia disorder (OR 2.1), alcohol abuse/dependence (OR 3.5), major depressive disorder (MDD) (OR 3.5), obsessive-compulsive disorder (OCD) (OR 3.9), or using over-the-counter sleeping pills (OR 2.5) or selective serotonin reuptake inhibitor (SSRI) antidepressants (OR 3.0) were at higher risk of frequent NW episodes (?2 times/month).With a rate of 29.2%, lifetime prevalence of NW is high. SSRIs were associated with an increased risk of NW. However, these medications appear to precipitate events in individuals with a prior history of NW. Furthermore, MDD and OCD were associated with significantly greater risk of NW, and this was not due to the use of psychotropic medication. These psychiatric associations imply an increased risk due to sleep disturbance.

Determining the level of sleepiness in the American population and its correlatesJOURNAL OF PSYCHIATRIC RESEARCHOhayon, M. M.2012; 46 (4): 422-427

Abstract

To assess the prevalence, to determine the risk factors and to evaluate the impacts of excessive sleepiness in the general population.It is a cross-sectional telephone study using a representative sample consisting of 8937 non-institutionalized individuals aged 18 or over living in Texas, New York and California. They represented a total of 62.8 million inhabitants. The participation rate was 85.6% in California, 81.3% in New York and 83.2% in Texas. Interviews were managed by the Sleep-EVAL expert system. The questionnaire included questions on sleeping habits, life habits, health, DSM-IV mental disorders, DSM-IV and ICSD sleep disorders.As many as 19.5% of the sample reported having moderate excessive sleepiness and 11.0% reported severe excessive sleepiness. Moderate excessive sleepiness was comparable between men and women but severe excessive sleepiness was higher in women (8.6% vs. 13.0%). Factors associated with moderate excessive sleepiness were sleeping 6 h or less per main sleep episode (OR:2.0); OSAS (OR:2.0); insomnia disorder (OR:2.4); Restless Legs Syndrome (OR: 1.8) major depressive disorder (OR: 1.7); anxiety disorder (OR:1.5) and use of tricyclic antidepressant (OR: 2.1) presence of heart disease (OR: 1.5), cancer (1.8) and chronic pain (1.3). Factors associated with severe excessive sleepiness were similar with the addition of being a woman (OR:1.5), alcohol dependence (OR: 1.4), bipolar disorder (OR: 2.1), use of over-the-counter sleeping pills (OR: 2.5), narcotic analgesics (OR: 3.4), Antidepressants (other than SSRI or tricyclic) and presence of gastro-esophageal reflux disease (OR:1.6). Sleepy individuals were twice as likely than non-sleepy participants to have had accidents while they were at the wheel of a vehicle during the previous year.Excessive sleepiness is highly prevalent in the American population. It was strongly associated with insufficient sleep and various sleep disorders as well as mental and organic diseases.

Prevalence and comorbidity of chronic pain in the German general populationJOURNAL OF PSYCHIATRIC RESEARCHOhayon, M. M., Stingl, J. C.2012; 46 (4): 444-450

Abstract

The objectives of this study were to evaluate 1) the prevalence of chronic and neuropathic pain features (NeP); 2) their comorbidities with psychiatric disorders and organic diseases; and 3) their impact on daily life and health care utilization. A random sample of 3011 participants (?15 years), representative of Germany, was interviewed by telephone. Chronic pain duration was set at three months. Neuropathy, frequency, severity, duration, impacts on functioning, and health care utilizations were investigated. Psychiatric disorders were assessed using DSM-IV-TR criteria. ICD-10 was used for organic diseases. Overall, 26.8% (95% confidence interval: 25.2-28.4%) of the sample reported having pain; 1.9% had acute pain (i.e., lasting less than three months), setting the prevalence of chronic pain at 24.9%. More precisely, 18.4% of the sample had non-neuropathic chronic pain (non-NeP) and 6.5% had NeP features. NeP presented several differences from non-NeP: individuals NeP features reported higher pain severity and higher interference of pain in daily activities compared to the non-NeP group. Individuals suffering from a major depressive disorder were three times more likely to have non-NeP and six times more likely to have NeP features. Individuals with obesity, diabetes, hypertension, cerebrovascular diseases, diseases of the nervous system, and diseases of the blood and blood-forming organs were at higher risk of having NeP but not non-NeP. These differences in prevalence and comorbidities between non-NeP and NeP features show how important it is to regard these different modalities of pain separately. Participants with NeP features suffer more and have greater impairment in their daily life than those with non-NeP.

Operational Definitions and Algorithms for Excessive Sleepiness in the General Population Implications for DSM-5 NosologyARCHIVES OF GENERAL PSYCHIATRYOhayon, M. M., Dauvilliers, Y., Reynolds, C. F.2012; 69 (1): 71-79

Abstract

Excessive sleepiness (ES) is poorly defined in epidemiologic studies, although its adverse implications for safety, health, and optimal social and vocational functioning have been extensively reported.To determine the importance of ES definition, measurement, and prevalence in the general population, together with its coexisting conditions.Cross-sectional telephone study.A total of 15 929 individuals representative of the adult general population of 15 states in the United States.Interviews were carried out using Sleep-EVAL, a knowledge-based expert system for use in epidemiologic studies, focusing on sleep, as well as physical and mental disorders, according to classification in DSM-IV and the second edition of the International Classification of Sleep Disorders. The interviews elicited information on ES, naps, frequency, duration, impairment, and distress associated with ES symptoms.Excessive sleepiness was reported by 27.8% (95% CI, 27.1%-28.5%) of the sample. Excessive sleepiness with associated symptoms was found in 15.6% of the participants (95% CI, 15.0%-16.2%). Adding an ES frequency of at least 3 times per week for at least 3 months despite normal sleep duration dropped the prevalence to 4.7% of the sample (95% CI, 4.4%-5.0%). The proportion of individuals having social or professional impairment and psychological distress increased with the frequency of ES symptoms during the week and within the same day. In multivariate models, the number of ES episodes per day and severity of ES were identified as the best predictors for impairment/distress. Prevalence of hypersomnia disorder was 1.5% of the participants (95% CI, 1.3%-1.7%). The most common coexisting conditions were mood and substance use disorders.Excessive sleepiness is an important problem in the US population, even when using restrictive criteria to define it. Hypersomnia disorder is more prevalent than previously estimated. Excessive sleepiness has to be recognized and given attention by public health authorities, scientists, and clinicians.

Abstract

To explore how insomnia symptoms are hierarchically organized in individuals reporting daytime consequences of their sleep disturbances.This is a cross-sectional study conducted in the general population of the states of California, New York, and Texas. The sample included 8937 individuals aged 18 years or older representative of the general population. Telephone interviews on sleep habits and disorders were managed with the Sleep-EVAL expert system and using DSM-IV and ICSD classifications. Insomnia symptoms and global sleep dissatisfaction (GSD) had to occur at least three times per week for at least three months.A total of 26.2% of the sample had a GSD. Individuals with GSD reported at least one insomnia symptom in 73.1% of the cases. The presence of GSD in addition to insomnia symptoms considerably increased the proportion of individuals with daytime consequences related to insomnia. In the classification trees performed, GSD arrived as the first predictor for daytime consequences related to insomnia. The second predictor was nonrestorative sleep followed by difficulty resuming sleep and difficulty initiating sleep.Classification trees are a useful way to hierarchically organize symptoms and to help diagnostic classifications. In this study, GSD was found to be the foremost symptom in identifying individuals with daytime consequences related to insomnia.

Abstract

The objective of this study is to assess the impact of nocturia on sleep in patients with lower urinary tract symptoms (LUTS)/benign prostatic enlargement (BPE) (nocturia?2).Cross-sectional survey.798 urologists and general practitioners randomly selected from the overall population of urologists and general practitioners of every French region.A total of 2179 LUTS/BPE men (aged 67.5±7.5 years old) were recruited. PRIMARY AND SECONDARY OUTCOME MEASURES: Validated patients' self-administered questionnaires were used to assess the severity of LUTS/BPE (the International Prostate Symptom Score), sleep characteristics (sleep log) and sleep disorders (the International Classification of Sleep Disorders (ICSD-2) and the DSM-IV). Sleepiness was assessed with the Epworth Sleepiness Scale (ESS). The volume of 24 h diuresis (1500 ml) was measured.Participants had on average 2.9±0.9 nocturia episodes (three or more episodes in 67%) and the International Prostate Symptom Score of 15.8±5.7; 60.9% complained of insomnia according to the ICSD-2, 7.9% of restless leg syndrome and 6.4% of obstructive sleep apnoea. 32.3% had excessive sleepiness (ESS >10) and 3.1% severe excessive sleepiness (ESS >16). Insomnia was mainly nocturnal awakenings with an average wake after sleep onset of 89±47 min. The number of episodes of nocturia per night correlated significantly with wake after sleep onset and ESS but not with total sleep time and sleep latency.Nocturia is significantly associated with sleep maintenance insomnia and sleepiness in men with BPE.

Abstract

This article reviews the literature pertaining to the association between demographic variables (e.g., age, sex, race, socio-economic status) with fatigue, and when feasible, accident risk. It also explores their potential influence and interaction with some working arrangements, commute time, personality characteristics, and circadian chronotype. Fatigue has been implicated in a range of impairments that can have detrimental effects on individuals, and it is differentially associated with conventional demographic variables. However, several major methodological limitations prevent clear conclusions. First, there is absence of a shared definition both within and across disciplines. Second, although fatigue has been investigated using a variety of diverse designs, they have either been too weak to substantiate causality or lacked ecological validity. Third, while both subjective and objective measures have been used as dependent variables, fatigue has been more often found to be more strongly linked with the former. Fourth, with the exception of age and sex, the influence of other demographic variables is unknown, since they have not yet been concomitantly assessed. In instances when they have been assessed and included in statistical analyses, they are considered as covariates or confounders; thus, their contribution to the outcome variable is controlled for, rather than being a planned aspect of investigation. Because the interaction of demographic factors with fatigue is largely a neglected area of study, we recommend greater interdisciplinary collaborations, incorporation of multiple demographic variables as independent factors, and use of within-participant analyses. These recommendations would provide meaningful results that may be used to inform public policy and preventive strategies.

Abstract

Sleep disorders and various common acute and chronic medical conditions directly or indirectly affect the quality and quantity of one's sleep or otherwise cause excessive daytime fatigue. This article reviews the potential contribution of several prevalent medical conditions - allergic rhinitis, asthma, chronic obstructive pulmonary disease, rheumatoid arthritis/osteoarthritis - and chronic fatigue syndrome and clinical sleep disorders - insomnia, obstructive sleep apnea, narcolepsy, periodic limb movement of sleep, and restless legs syndrome - to the risk for drowsy-driving road crashes. It also explores the literature on the cost-benefit of preventive interventions, using obstructive sleep apnea as an example. Although numerous investigations have addressed the impact of sleep and medical disorders on quality of life, few have specifically addressed their potential deleterious effect on driving performance and road incidents. Moreover, since past studies have focused on the survivors of driver crashes, they may be biased. Representative population-based prospective multidisciplinary studies are urgently required to clarify the role of the fatigue associated with common ailments and medications on traffic crash risk of both commercial and non-commercial drivers and to comprehensively assess the cost-effectiveness of intervention strategies.

Nocturnal awakenings and difficulty resuming sleep: Their burden in the European general populationJOURNAL OF PSYCHOSOMATIC RESEARCHOhayon, M. M.2010; 69 (6): 565-571

Abstract

To (1) define the prevalence and importance of nocturnal awakenings (NA) in the general population, and (2) investigate its associations with daytime impairment, physical diseases, and psychiatric disorders.This is a cross-sectional telephone study conducted in the general population of France, United Kingdom, Germany, Italy, and Spain. A representative sample consisting of 22,740 non-institutionalized individuals aged 15 or over was interviewed regarding sleeping habits, health, sleep and mental disorders. Nocturnal awakenings were evaluated according to their frequency per week and per night and their duration.At the time of the interview, 31.2% (95% confidence interval: 30.6-31.8%) of the sample reported waking up at least 3 nights per week and 7.7% (7.4% to 8.0%) of the sample had difficulty resuming sleep (DRS) after they woke up. Duration of the symptom was longer than one year in 78.8% of the cases. DRS had greater impacts on daytime functioning than any other kind of NA or other insomnia symptoms with odds ratios five to seven times higher than individuals waking up once or twice within the same night. Individuals with painful physical condition or with a psychiatric disorder were more than four times more likely to have DRS. Other significant factors associated with NA were hypertension, cardio-vascular disease, upper airway disease, diabetes, and heavy caffeine consumption.Nocturnal awakenings are highly prevalent in the general population and strongly associated with various physical diseases and psychiatric disorders. There is also a dose response effect in the associations: odds ratios increased with the number of awakenings during the same night and the difficulty resuming sleep once awakened. The study shows that nocturnal awakenings are complex and should be assessed systematically.

Prevalence of insomnia and sleep characteristics in the general population of SpainSLEEP MEDICINEOhayon, M. M., Sagales, T.2010; 11 (10): 1010-1018

Abstract

The goals of this study were to estimate the prevalence of insomnia symptomatology and diagnoses in the Spanish general population and to determine if certain sleep parameters were related to specific insomnia symptoms.This is a cross-sectional telephone survey performed in the general population of Spain using a representative sample of 4065 individuals aged 15years or older. The participation rate was 87.5%. Interviews were conducted using the Sleep-EVAL system. The questions were related to sociodemographic characteristics, sleep-wake schedule, events occurring during sleep, insomnia symptoms, daytime consequences and DSM-IV diagnoses of sleep disorders.Overall, 20.8% (95% C.I. 19.6-22.1%) of the sample reported at least one insomnia symptom occurring at least three nights/week. The prevalence was higher in women than in men (23.9% vs. 17.6%) and increased with age. Difficulty maintaining sleep at least three nights/week was the most prevalent symptom. DSM-IV insomnia disorder diagnoses were found in 6.4% (95% C.I. 5.6-7.1%) of the sample. Delayed bedtime and wake-up time, irregular bedtime hours and hypnagogic hallucinations were the most frequent in participants who had difficulty initiating sleep. Perception of light and "too short" sleep were the most frequent in participants who had early morning awakenings. Participants who had a non-restorative sleep were more likely to extend sleep on days off than other insomnia participants. Medical consultations in the previous year were more frequent in insomnia participants compared to participants without insomnia. One-fifth of insomnia participants were using sleep-promoting medication.Insomnia is frequent in Spain, affecting up to one in five individuals. Results show that insomnia is multidimensional and needs to be assessed as such.

Abstract

Despite convincing evidence regarding the risk of highway accidents due to sleepiness at the wheel, highway drivers still drive while sleepy. Sleep disorders can affect driving skills, but the relative impact of sleep complaints among a large population of highway drivers is still unknown.Out of 37,648 questionnaires completed by frequent highway users (registered in an electronic payment system), we ran our analyses on 35,004 drivers who responded to all items. The questionnaire previously used in a telephone survey included socio-demographics, driving and sleep disorders items (Basic Nordic Sleep Questionnaire) and the Epworth Sleepiness Scale.Of all drivers, 16.9% complained of at least one sleep disorder, 5.2% reported obstructive sleep apnea syndrome, 9.3% insomnia, and 0.1% narcolepsy and hypersomnia; 8.9% of drivers reported experiencing at least once each month an episode of sleepiness at the wheel so severe they had to stop driving. One-third of the drivers (31.1%) reported near-miss accidents (50% being sleep-related), 2520 drivers (7.2%) reported a driving accident in the past year, and 146 (5.8%) of these driving accidents were sleep-related. The highest risk of accidents concerned patients suffering from narcolepsy and hypersomnia (odds ratio 3.16, p

Abstract

To assess the prevalence of insomnia symptoms, their associated factors and daytime symptoms in the general population of Sweden.This is a cross-sectional postal survey performed in the general population of Sweden aged between 19 and 75 years (6 million inhabitants). A total of 1209 out of 1705 randomly selected participants from the National Register of the Total Population completed the questionnaire. The participation rate was 71.3%. Participants filled out a paper-pencil questionnaire composed of 157 items covering sociodemographic characteristics, sleeping habits and environment, sleep quality and sleep symptoms, and health status.We found 32.1% (95% confidence interval: 29.5-34.8%) of the sample reported having difficulty initiating (DIS) or maintaining sleep (DMS) or non-restorative sleep accompanied with sufficient sleep (NRS) at least 4 nights per week: 6.3% of the sample had DIS, 14.5% had DMS and 18.0% had NRS. Results from logistic regressions showed that restless legs symptoms, breathing pauses during sleep and depressive or anxious mood were associated with DIS and DMS but not NRS. Living in an urban area (OR:2.0) and drinking alcohol daily (OR:4.6) were associated only with NRS. Daytime symptoms were reported by over 75% of subjects with insomnia symptoms. DIS, DMS and NRS were associated with daytime fatigue but not excessive sleepiness as measured by the Epworth scale. DIS was associated with the use of sleeping pills or natural sleeping aid compounds in multivariate models.Insomnia symptoms occurring at least 4 nights per week are frequent in Sweden, affecting about a third of the population. Subjects with NRS have a distinctly different profile than those with DIS or DMS, which suggests different etiological causes for this symptom.

Abstract

Violent behaviors during sleep (VBS) are consequences of several sleep disorders but have received little attention in epidemiologic studies. This study aims to determine the prevalence of VBS in the general population and their comorbidity, familial links, course and treatment.Random stratified sample of 19,961 participants, 15 years and older, from the general population of Finland, Germany, Italy, Portugal, Spain and the United Kingdom were interviewed by telephone using the Sleep-EVAL Expert System. They answered a questionnaire on VBS, their consequences and treatment. Parasomnias and sleep and mental disorders were also evaluated.VBS was reported by 1.6% (95% confidence interval: 1.4-1.7%) of the sample. VBS was higher in subjects younger than 35 years. During VBS episodes, 78.7% of VBS subjects reported vivid dreams and 31.4% hurt themselves or someone else. Only 12.3% of them consulted a physician for these behaviors. In 72.8% of cases, VBS were associated with other parasomnias (highest odds of VBS for sleepwalking and sleep terrors). Family history of VBS, sleepwalking and sleep terrors was reported more frequently in VBS than in non-VBS subjects with odds of 9.3, 2.0 and 4.2, respectively.VBS are frequent in the general population and often associated with dream-enactment, sleepwalking and sleep terrors. High frequency of VBS, sleepwalking and sleep terrors in family of VBS subjects indicated that some families have a greater vulnerability to sleep disorders involving motor dyscontrol. Subjects who consulted a physician for these behaviors mostly received inappropriate or no support, indicating a lack of knowledge about VBS.

Abstract

This study aims (1) to assess the prevalence of Chronic Painful Physical Condition (CPPC) and major depressive disorder (MDD) in the general population; (2) to evaluate their interaction and co-morbidity with sleep and organic disorders; and (3) to investigate their daily functioning and socio-professional consequences. A random sample of 3243 subjects (18years), representative of California inhabitants, was interviewed by telephone. CPPC duration was at least 6months. Frequency, severity, duration and consequences on daily functioning, consultations, sick leave and treatment were investigated. MDD were assessed using DSM-IV criteria. The point prevalence of CPPC was 49% (95% confidence interval: 47.0-51.0%). Back area pain was the most frequent; 1-month prevalence of MDD was at 6.3% (95% CI: 5.5-7.2%); 66.3% of MDD subjects reported at least one CPPC. In 57.1% of cases, pain appeared before MDD. Pain severity was increased by poor sleep, stress and tiredness in MDD subjects. Being confined to bed, taking sick leave and interference of pain with daily functioning were twice as frequent among MDD subjects with CPPC than in non-MDD subjects with CPPC; obese individuals with CP were 2.6 times as likely to have MDD. Pain is highly linked with depressive disorder. It deteriorates physical, occupational and socio-professional activities. Pain and sleep disturbances are a prime motive of consultation rather than depressed mood, underlining the risk of missing a depression diagnosis.

Abstract

Nocturnal awakenings are one of the most prevalent sleep disturbances in the general population. Little is known, however, about the frequency of these episodes and how difficulty resuming sleep once awakened affects subjective sleep quality and quantity.This is a cross-sectional telephone study with a representative sample consisting of 8937 non-institutionalized individuals aged 18 or over living in Texas, New York and California. The interviews included questions on sleeping habits, health, sleep and mental disorders. Nocturnal awakenings were evaluated according to their frequency per week and per night, as well as their duration.A total of 35.5% of the sample reported awakening at least three nights per week. Of this 35.5%, 43% (15.2% of the total sample) reported difficulty resuming sleep once awakened. More than 80% of subjects with insomnia symptoms (difficulty initiating or maintaining sleep or non-restorative sleep) also had nocturnal awakenings. Difficulty resuming sleep was associated with subjective shorter sleep duration, poorer sleep quality, greater daytime impairment, greater consultations for sleep disturbances and greater likelihood of receiving a sleep medication.Nocturnal awakenings disrupt the sleep of about one-third of the general population. Using difficulty resuming sleep identifies individuals with significant daytime impairment who are most likely to seek medical help for their sleep disturbances. In the absence of other insomnia symptoms, nocturnal awakenings alone are unlikely to be associated with daytime impairments.

Abstract

Social phobia may seriously impair the functioning of affected individuals. It is frequently associated with other mental disorders.To estimate the co-occurrence of social phobia with major depressive disorder (MDD) and to analyze their interaction.Subjects were 18,980 individuals, aged 15 years or older, representative of the general population of the United Kingdom, Germany, Italy, Spain and Portugal, who were interviewed by telephone. DSM-IV diagnoses were made with the Sleep-EVAL system.The point prevalence for social phobia was 4.4% (95% confidence interval: 4.1-4.7%) of the sample. It was higher in women (odds ratio: 1.6) and decreased with age. MDDs were found in 19.5% of participants with social phobia. Co-occurrence of another anxiety disorder was high and increased when a MDD was present (65.2%). The odds of developing a major depressive episode 2 years after the appearance of the social phobia was of 5.74.Social phobia is highly prevalent in the general population. It increases the risk of developing a MDD and has a high comorbidity with other mental disorders. Social phobia is often present in the course of depression, more obviously during remission period of MDD. Physicians must explore and treat more systematically this frequent pathology.

Abstract

Rotating shift and permanent night work arrangements are known to compromise sleep. This study examined the effects of work schedule on sleep duration, excessive sleepiness, sleep attacks, driving, and domestic/professional accidents. A representative sample of the general population of the state of New York--3,345 individuals > or = 18 yrs of age--was interviewed by telephone regarding their sleep and psychiatric and organic disorders. Multivariate models were applied to derive odds ratios (OR) after adjustment for age, sex, physical illness, mental disorders, obstructive sleep apnea, and sleep duration. On average (+/-SE), workers slept 6.7 +/- 1.5 h, but 40% slept < 6.5 h/main sleep episode. Short-sleep duration (< 6 h) was strongly associated with fixed night (OR: 1.7) and day-evening-night shiftwork arrangement (OR: 1.9). Some 20% of the workers manifested excessive sleepiness in situations requiring high attention, and it was associated with the fixed night (OR: 3.3) and day-evening-night work arrangements (OR: 1.5). Overall, 5% of the workers reported sleep attacks; however, they occurred three-times more frequently in the fixed night (15.3%) than other work arrangements (OR: 3.2). Driving accidents during the previous 12 months were reported by 3.6% of the workers and were associated with fixed night (OR: 3.9) and day-evening-night (OR: 2.1) work schedules. The findings of this study indicate that working outside the regular daytime hours was strongly associated with shorter sleep duration, sleepiness, and driving accident risk. Night work is the most disrupting, as it is associated with insufficient sleep during the designated rest span and excessive sleepiness and sleep attacks during the span of activity, with an associated consequence being increased driving accident risk.

Epidemiological and clinical relevance of insomnia diagnosis algorithms according to the DSM-IV and the International Classification of Sleep Disorders (ICSD)SLEEP MEDICINEOhayon, M. M., Reynolds, C. F.2009; 10 (9): 952-960

Abstract

Although the epidemiology of insomnia in the general population has received considerable attention in the past 20 years, few studies have investigated the prevalence of insomnia using operational definitions such as those set forth in the ICSD and DSM-IV, specifying what proportion of respondents satisfied the criteria to reach a diagnosis of insomnia disorder.This is a cross-sectional study involving 25,579 individuals aged 15 years and over representative of the general population of France, the United Kingdom, Germany, Italy, Portugal, Spain and Finland. The participants were interviewed on sleep habits and disorders managed by the Sleep-EVAL expert system using DSM-IV and ICSD classifications.At the complaint level, too short sleep (20.2%), light sleep (16.6%), and global sleep dissatisfaction (8.2%) were reported by 37% of the subjects. At the symptom level (difficulty initiating or maintaining sleep and non-restorative sleep at least 3 nights per week), 34.5% of the sample reported at least one of them. At the criterion level, (symptoms+daytime consequences), 9.8% of the total sample reported having them. At the diagnostic level, 6.6% satisfied the DSM-IV requirement for positive and differential diagnosis. However, many respondents failed to meet diagnostic criteria for duration, frequency and severity in the two classifications, suggesting that multidimensional measures are needed.A significant proportion of the population with sleep complaints do not fit into DSM-IV and ICSD classifications. Further efforts are needed to identify diagnostic criteria and dimensional measures that will lead to insomnia diagnoses and thus provide a more reliable, valid and clinically relevant classification.

Difficulty in resuming or inability to resume sleep and the links to daytime impairment: Definition, prevalence and comorbidityJOURNAL OF PSYCHIATRIC RESEARCHOhayon, M. M.2009; 43 (10): 934-940

Abstract

To assess the chronicity and severity of nocturnal awakenings with difficulty resuming sleep (DRS), its value as an indicator of an ongoing sleep and/or mental disorder and, finally, how it affects on daytime functioning.A cross-sectional telephone study was performed in the non-institutionalized general population of France, the United Kingdom, Germany, Italy and Spain. This representative sample of 22,740 non-institutionalized individuals aged 15 or over was interviewed on their sleeping habits, health, sleep and mental disorders. These five European countries totaled 245.1 million inhabitants. The evaluation of nocturnal awakenings with DRS included duration, frequency (per night, per week and in the previous months) and assessment scale of daytime functioning. DRS was defined as a complaint of difficulty in resuming or inability to resume sleep occurring at least three nights per week and lasting for at least one month.A total of 16.1% [95% CI: 15.6-16.6] of the sample had DRS. Prevalence was higher in women and increased with age. The average duration of DRS was 40 months. DRS individuals slept on average 30 min less than other subjects with insomnia symptoms and 60 min less than the rest of the sample. Painful physical conditions, anxiety and mood disorders were the most discriminative factors for individuals with DRS distinguishing them from other insomnia subjects and the rest of the sample. Daytime impairment was observed in 52.2% of DRS individuals compared to 32.8% in individuals with classical insomnia symptoms (p < 0.0001).(1) DRS affect a large segment of the population; (2) it is a good indicator of an ongoing sleep or mental disorder; (3) it has a stronger impact on daytime functioning than classical insomnia symptoms (OR: 4.7).

Nocturnal awakenings and comorbid disorders in the American general populationJOURNAL OF PSYCHIATRIC RESEARCHOhayon, M. M.2008; 43 (1): 48-54

Abstract

Nocturnal awakenings are one of the most prevalent sleep disturbances in the general population. However, little is know about how its severity affects co-morbidity with mental disorders and organic diseases.A representative sample consisting of 8937 non-institutionalized individuals aged 18 or over living in Texas, New York and California states were interviewed by telephone. The interviews included sleeping habits, health, sleep and mental disorders. Nocturnal awakenings were evaluated according to their frequency per week and per night, their duration and the motive(s) for the awakenings.A total of 35.5% of the sample reported awakening at least 3 nights per week: 23% of reported awakening at least one time every night; 4.5% 5 or 6 nights per week and 7.9% 3 or 4 nights per week. Nocturnal awakenings increased with age only among people with nightly awakenings and were more frequent among women than men only among those awakening every night. More than 90% of subjects reported this problem lasted for more than 6 months. About 40% of subjects with nocturnal awakenings also reported other insomnia symptoms. Generally speaking, organic diseases and psychiatric disorders were more frequent among subjects waking up at least 3 nights per week regardless the frequency of nocturnal awakenings. However, nightly nocturnal awakenings were associated with more frequent organic diseases, obesity and psychiatric disorders.Nocturnal awakenings disrupt the sleep of about one third of the general population. Nocturnal awakenings are associated with a wide variety of organic diseases and psychiatric disorders that warrant appropriate treatment.

From wakefulness to excessive sleepiness: What we know and still need to knowSLEEP MEDICINE REVIEWSOhayon, M. M.2008; 12 (2): 129-141

Abstract

The epidemiological study of hypersomnia symptoms is still in its infancy; most epidemiological surveys on this topic were published in the last decade. More than two dozen representative community studies can be found. These studies assessed two aspects of hypersomnia: excessive quantity of sleep and sleep propensity during wakefulness excessive daytime sleepiness. The prevalence of excessive quantity of sleep when referring to the subjective evaluation of sleep duration is around 4% of the population. Excessive daytime sleepiness has been mostly investigated in terms of frequency or severity; duration of the symptom has rarely been investigated. Excessive daytime sleepiness occurring at least 3 days per week has been reported in between 4% and 20.6% of the population, while severe excessive daytime sleepiness was reported at 5%. In most studies, men and women are equally affected. In the International Classification of Sleep Disorders, hypersomnia symptoms are the essential feature of three disorders: insufficient sleep syndrome, hypersomnia (idiopathic, recurrent or posttraumatic) and narcolepsy. Insufficient sleep syndrome and hypersomnia diagnoses are poorly documented. The co-occurrence of insufficient sleep and excessive daytime sleepiness has been explored in some studies and prevalence has been found in around 8% of the general population. However, these subjects often have other conditions such as insomnia, depression or sleep apnea. Therefore, the prevalence of insufficient sleep syndrome is more likely to be between 1% and 4% of the population. Idiopathic hypersomnia would be rare in the general population with prevalence, around 0.3%. Narcolepsy has been more extensively studied, with a prevalence around 0.045% in the general population. Genetic epidemiological studies of narcolepsy have shown that between 1.5% and 20.8% of narcoleptic individuals have at least one family member with the disease. The large variation is mostly due to the method used to collect the information on the family members; systematic investigation of all family members provided higher results. There is still a lot to be done in the epidemiological field of hypersomnia. Inconsistencies in its definition and measurement limit the generalization of the results. The use of a single question fails to capture the complexity of the symptom. The natural evolution of hypersomnia remains to be documented.

Abstract

Sleep disorders can be expressed in different ways. The International Classification of Sleep Disorders lists more than 80 different sleep disorder diagnoses. In general population, although the insomnia complaint is reported by nearly the third of the population, it is translated into a diagnosis of insomnia for only 6% to 15% of the population. Sleep apnea syndrome, often associated with insomnia or daytime sleepiness, is found in approximately 2% to 4% of the general population. Restless legs syndrome is present for approximately 6% of the general population with a higher prevalence in the elderly subject. Narcolepsy is rare with a prevalence of 0.04%. Parasomnias are less studied in the general population; prevalences of several of parasomnias remain unknown. Among those more extensively studied, sleep paralysis is found for approximately 6% of the general population. Nocturnal terrors, the confusional arousals and nightmares have been observed with prevalences ranging from 2.2% to 5%. Despite their high frequency, sleep disorders remain poorly identified; less than 20% of individuals with sleep disorders are correctly diagnosed and treated.

Epidemiology of depression and its treatment in the general populationJOURNAL OF PSYCHIATRIC RESEARCHOhayon, M. M.2007; 41 (3-4): 207-213

Abstract

This study examines the correlates of a major depressive disorder and its treatment in the general population. The sample was composed of 6694 individuals aged between 18 and 96 years, representative of the general population of the states of California and New York (48 million inhabitants aged 18 years or older). They were interviewed by telephone using the Sleep-EVAL system. The interviews included various sleep and health topics and the assessment of DSM-IV sleep and psychiatric disorders. The 1-month prevalence of a major depressive disorder was 5.2% in the sample, and was higher in women, middle-aged and non-Hispanic white individuals. Obesity (BMI > or =30kg/m(2)), poor health status and smoking were also strongly correlated with a major depressive disorder. A total of 57.7% of depressed subjects were receiving some forms of treatment for depression: 28.3% were taking antidepressants (alone or in combination with psychiatric health care) and 29.4% received psychiatric health care (without antidepressant medication). Severity of depression, ethnicity and weight (overweight or obese) were strongly associated with the presence of treatment. A major depressive disorder is frequent in the general population. Although its identification and treatment have improved over the years, some segments of the population, namely elderly and non-white individuals are less likely to receive appropriate care.

Abstract

First-degree relatives of narcoleptic subjects (probands) may have sleep pathology related to the transmission of the disorder through their family members. The authors examined four groups: probands (n = 96), first-degree relative (n = 337), environmental reference (n = 85), and general population (n = 6,694) groups. Compared with the general population, family members have a 75-fold increased risk for narcolepsy. They are also at greater risk for insufficient sleep syndrome (odds ratio [OR] 6.1), nocturnal eating (OR 5.7), and adjustment sleep disorder (OR 3.1).

Abstract

Because hot flashes can occur during the night, their presence has been frequently associated with insomnia in women with symptoms of menopause. However, many factors other than hot flashes or menopause can be responsible for insomnia, and several factors associated with insomnia in the general population are also commonly observed in perimenopausal and postmenopausal women who have hot flashes.A random sample of 3243 subjects (aged > or =18 years) representative of the California population was interviewed by telephone. Included were 982 women aged 35 to 65 years. Women were divided into 3 groups according to menopausal status: premenopause (57.2%), perimenopause (22.3%), and postmenopause (20.5%). Hot flashes were counted if they were present for at least 3 days per week during the last month and were classified as mild, moderate, or severe according to their effect on daily functioning. Chronic insomnia was defined as global sleep dissatisfaction, difficulty initiating sleep, difficulty maintaining sleep, or nonrestorative sleep, for at least 6 months. Diagnoses of insomnia were assessed according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, classification.Prevalence of hot flashes was 12.5% in premenopause, 79.0% in perimenopause, and 39.3% in postmenopause. Prevalence of chronic insomnia was reported as 36.5% in premenopause, 56.6% in perimenopause, and 50.7% in postmenopause (P

Abstract

This prospective study aimed to assess symptomatic evolution of patients diagnosed with Upper Airway Resistance Syndrome (UARS) four and half years after the initial UARS diagnosis. For this purpose, 138 UARS patients were contacted by mail between 43 and 69 months after the initial evaluation; 105 responded to the letter and 94 patients accepted to undergo new clinical and polysomnographic evaluations. Initial and follow-up polysomnographic recordings were scored using the same criteria.Of the 94 patients who completed the follow-up examination, none of them were using nasal CPAP. It was related to refusal by insurance providers to provide equipment based on initial apnea-hypopnea index (AHI) in 90/94 subjects. Percentage of patients with sleep related-complaints significantly increased over the four and half year period: daytime fatigue, insomnia and depressive mood increased by 12 to 20 times. Reports of sleep maintenance sleep onset insomnia and depressive mood was significantly increased. Hypnotic, antidepressant and stimulant prescription increased from initial to follow-up visit (from 11.7% to 61.7%; from 3.2% to 25.5% and from 0% to 9.6%, respectively) with antidepressant given as much for sleep disturbance as mood disorder. The polysomnography results at follow-up showed that 5 subjects had AHI compatible with Obstructive Sleep Apnea Syndrome (OSAS) but overall, respiratory disturbance index had no significant change. Total sleep time was significantly reduced compared to initial visit.Many UARS patients remained untreated following initial evaluation. Worsening of symptoms of insomnia, fatigue and depressive mood were seen with absence of treatment of UARS.

Prevalence of major depressive disorder in the general population of South KoreaJOURNAL OF PSYCHIATRIC RESEARCHOhayon, M. M., Hong, S. C.2006; 40 (1): 30-36

Abstract

Previous epidemiological studies have reported a high prevalence of major depressive disorder (MDD) in North America and Western Europe. However, little information exists on MDD in Asian countries. This study investigates the prevalence of MDD and its characteristics in the general population of South Korea.A representative sample of the South Korean general population composed of 3719 non-institutionalized individuals aged 15 years or older was interviewed by telephone using the Sleep-EVAL system. The participation rate was 91.4%. The interviews covered sociodemographic characteristics, health care utilization, physical illnesses and Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) psychiatric disorders.A depressive mood, i.e., feeling sad, downcast, having the blues or having lost interest in things formerly pleasant was reported by 20.9% of the sample without significant difference between men and women and among age groups. DSM-IV MDD was found in 3.6% (95% CI: 3.0-4.2%) of the sample. The prevalence of MDD was comparable among age groups. Shift workers were more likely to have MDD than daytime workers. Factor significantly associated with MDD were: being a woman, being a light or heavy smoker, perceiving one's health as being average or poor, doing physical activities at least three times per week in the evening, having a BMI below 18.5 kg/m2 and perceiving one's life as being moderately or highly stressful.Prevalence of MDD in Korea is higher than what it was previously estimated to be two decades ago. The number of individuals seeking help for depression was very low, and only a small number of MDD subjects received appropriate treatment for their condition.

Abstract

Narcolepsy is a rare neurological sleep disorder affecting around 0.05% of the general population. Genetic factors are known to have an important role in narcolepsy. However, because of its very low prevalence, it is difficult to have groups of comparison between first-degree relatives and general population subjects in order to identify a specific spectrum of disorders in these families. Consequently, from 157 Italian patients with narcolepsy, 263 first-degree relatives were recruited, two refused to participate. These family members were compared with a matched group of 1071 subjects selected from a sample of 3970 subjects representative of the general population of Italy (46 million inhabitants). Finally, 68 spouses of narcoleptic patients were used to assess for possible role of environmental factors. All subjects were interviewed by telephone using the Sleep-EVAL system. Nineteen cases of narcolepsy were discovered among the first-degree relatives of 17 probands (10.8%). Compared with the general population subjects, the relative risk of narcolepsy among female first-degree relatives was of 54.4 and of 105.1 among male first-degree relatives. First-degree relatives were also at higher risk for idiopatic hypersomnia (OR: 23.0), obstructive sleep apnea syndrome (OR: 6.8), adjustment sleep disorder (OR: 4.0), insufficient sleep syndrome (OR: 7.0), circadian rhythm disorders (OR: 2.5), REM behavior disorder (OR: 4.4), and sleep talking (OR: 2.0). The vulnerability to sleep disorders is very high in first-degree relatives and the link with different expressivity and severity of hypersomnia can be confirmed.

Abstract

The aim of this study was to investigate the influence of age on the manifestation of narcolepsy symptoms and cognitive difficulties in patients with narcolepsy.A total of 321 participants were included in the study: 157 were patients with narcolepsy from two Sleep Disorders Clinics and 164 were control participants. Narcoleptic patients were evaluated and diagnosed at the Sleep Disorders Clinic. All participants were interviewed by telephone using the Sleep-EVAL System. The interview comprised, among else, a detailed evaluation of narcolepsy symptoms and of cognitive difficulties.The first manifestation of the disease appeared early in life for most narcoleptic patients: 54.1% had their first symptom before the age of 20 years. Daytime sleepiness was the first symptom to appear in 65.5% of cases. In narcoleptics 60 years or older, cataplexy was more likely to be the first symptom to appear (47.4%) compared with other narcoleptic patients (21.4%; P

Global sleep dissatisfaction for the assessment of insomnia severity in the general population of PortugalSLEEP MEDICINEOhayon, M. M., Paiva, T.2005; 6 (5): 435-441

Abstract

This study examines the prevalence and associated factors of insomnia symptoms and sleep dissatisfaction in the general population of Portugal.We interviewed by telephone 1858 participants aged 18 years or older and representative of the general population of Portugal using the Sleep-EVAL system. Participation rate was 83%. The questionnaire included the assessment of sleep habits, insomnia symptomatology according to DSM-IV and ICSD classifications, associated and sleep/mental disorders and daytime consequences.Insomnia symptoms occurring at least 3 nights per week were reported by 28.1% of the sample and global sleep dissatisfaction (GSD) by 10.1%. Difficulty maintaining sleep was the most frequent symptom (21.0%); 29.4% of subjects with insomnia symptoms reported GSD. Daytime consequences, medical consultations for sleep and use of sleep medication were at least 2 times more frequent among subjects with insomnia symptoms and GSD compared to subjects with insomnia symptoms without GSD; insomnia diagnoses were also more frequent in the GSD group.The results show a severity gradation among subjects with only 1 insomnia symptom, those with 2 or 3 insomnia symptoms but without GSD and those with at least 1 insomnia symptom and GSD. Specific sleep or psychiatric disorders were identified for the majority of GSD subjects (86%); this rate dropped to 50.6% when only 1 insomnia symptom without GSD was reported. GSD appeared to be a good indicator of the presence of a sleep or psychiatric disorder and a good discriminator of the severity of sleep disturbances among subjects with insomnia symptoms.

Abstract

To present normative data of sleep-wake characteristics and to examine risk factors associated with extreme values (i.e., in the 5 lower and upper percentiles of the distribution) in older adults.Cross-sectional telephone surveyThe metropolitan area of Paris, France.A total of 7010 randomly selected households were contacted. Among them, 1264 households included at least 1 resident 60 years of age or older; 1026 subjects agreed to participate (participation rate: 80.9%).None.Subjects were interviewed with the Sleep-EVAL System about their sleeping habits and sleep and psychiatric disorders. In addition, the system administered to all the participants the Psychological General Well-Being Schedule, the Cognitive Difficulties Scale (Mac Nair-R), and an independent living scale. The median nighttime sleep duration was 7 hours without significant difference between the age groups. Factors positively associated with the 5 percentile (4 hours 30 minutes or less) of nighttime sleep duration were obesity, poor health, insomnia, and insomnia accompanied by daytime sleepiness and cognitive impairment. At the other extremity (95th percentile), long sleep (9 hours 30 minutes or more) was associated with organic disease, lack of physical exercise, and lower education. A daytime sleep duration of 1 hour or more (95th percentile) was associated with being a man, cognitive impairment, high blood pressure, obesity, and insomnia. Long sleep latency (95th percentile at 80 minutes) was associated with anxiety, lower education, poor health, insomnia without excessive daytime sleepiness, and obstructive sleep apnea syndrome. Obesity and loss of autonomy in activities of daily living was associated with both early (9 PM or earlier) and late bedtime (1 AM or later) and early (< or = 5 AM) and late (> or = 9 AM) wake-up time.This study illustrates the usefulness of normal distributions of sleep parameters in the general population to calculate different risk factors associated with extreme values of the normal distribution.

Abstract

A chronic painful physical condition (CPPC) can be a major cause of sleep disturbances. Few community-based surveys examined the specific relationship between these two conditions.Eighteen thousand, nine hundred and eighty participants aged 15 years or older from five European countries (the United Kingdom, Germany, Italy, Portugal and Spain) and representative of approximately 206 millions Europeans were interviewed by telephone. The interview included questions about sleeping habits, health, sleep and mental disorders. Painful physical conditions were ascertained through questions about medical treatment, consultations and/or hospitalizations for medical reasons and a list of 42 diseases. A painful physical condition was considered chronic when it lasted at least six months. Insomnia symptoms were defined as difficulty initiating or maintaining sleep or non-restorative sleep, present at least three nights per week, lasting at least one month, and accompanied by daytime consequences.(1) The point prevalence of at least one CPPC was set at 17.1% (95% CI: 16.5-17.6%) in the sample. (2) Difficulty initiating sleep was found in 5.1% (95% CI: 4.8-5.4%) of the sample, disrupted sleep in 7.5% (95% CI: 7.2-7.9%); early morning awakenings in 4.8% (95% CI: 7.2-7.9%) and non-restorative sleep in 4.5% (95% CI: 4.2-4.8%). (3) More than 40% of individuals with insomnia symptoms reported at least one CPPC. (4) CPPC was associated with more frequent difficulty or inability to resume sleep once awake and a shorter sleep duration. (5) In middle-aged subjects (45-64 years of age), CPPC was associated with longer insomnia duration. At any age, insomnia with CPPC was associated with a greater number of daytime consequences (average of four consequences) than in insomnia without CPPC (average of 2.3 consequences). (6) In multivariate models, CPPC, especially backaches and joint/articular diseases, were at least as importantly associated with insomnia than were mood disorders with odds ratios ranging from 4.1 to 5.0 for backaches and from 3.0 to 4.8 for joint/articular diseases.CPPC is associated with a worsening of insomnia on several aspects: a greater number of insomnia symptoms, more severe daytime consequences and more chronic insomnia situation. CPPC plays a major role on insomnia. Its place as major contributive factor for insomnia is as much important as mood disorders.

Abstract

Nonrestorative sleep (NRS) has been little studied in the general population, even though this symptom has an important role in several medical conditions such as heart disease, fibromyalgia, and chronic fatigue syndrome, as well as various sleep disorders.A total of 25,580 individuals (age range, 15-100 years) from the noninstitutionalized general population representative of 7 European countries (France, the United Kingdom, Germany, Italy, Portugal, Spain, and Finland) were interviewed by telephone using the Sleep-EVAL system. Nonrestorative sleep was analyzed in relationship to sociodemographic determinants, environmental factors, life habits, health, sleep-wake schedule, and psychological factors.The prevalence of NRS was 10.8% (95% confidence interval, 10.4%-11.2%) in the sample, was higher in women than in men (12.5% vs 9.0%; P

Abstract

The purposes of this study were to identify age-related changes in objectively recorded sleep patterns across the human life span in healthy individuals and to clarify whether sleep latency and percentages of stage 1, stage 2, and rapid eye movement (REM) sleep significantly change with age.Review of literature of articles published between 1960 and 2003 in peer-reviewed journals and meta-analysis.65 studies representing 3,577 subjects aged 5 years to 102 years.The research reports included in this meta-analysis met the following criteria: (1) included nonclinical participants aged 5 years or older; (2) included measures of sleep characteristics by "all night" polysomnography or actigraphy on sleep latency, sleep efficiency, total sleep time, stage 1 sleep, stage 2 sleep, slow-wave sleep, REM sleep, REM latency, or minutes awake after sleep onset; (3) included numeric presentation of the data; and (4) were published between 1960 and 2003 in peer-reviewed journals.In children and adolescents, total sleep time decreased with age only in studies performed on school days. Percentage of slow-wave sleep was significantly negatively correlated with age. Percentages of stage 2 and REM sleep significantly changed with age. In adults, total sleep time, sleep efficiency, percentage of slow-wave sleep, percentage of REM sleep, and REM latency all significantly decreased with age, while sleep latency, percentage of stage 1 sleep, percentage of stage 2 sleep, and wake after sleep onset significantly increased with age. However, only sleep efficiency continued to significantly decrease after 60 years of age. The magnitudes of the effect sizes noted changed depending on whether or not studied participants were screened for mental disorders, organic diseases, use of drug or alcohol, obstructive sleep apnea syndrome, or other sleep disorders.In adults, it appeared that sleep latency, percentages of stage 1 and stage 2 significantly increased with age while percentage of REM sleep decreased. However, effect sizes for the different sleep parameters were greatly modified by the quality of subject screening, diminishing or even masking age associations with different sleep parameters. The number of studies that examined the evolution of sleep parameters with age are scant among school-aged children, adolescents, and middle-aged adults. There are also very few studies that examined the effect of race on polysomnographic sleep parameters.

Abstract

Insomnia is a frequent symptom in the general population; numerous studies have proven this. In the past years, classifications have gradually given more emphasis to daytime repercussions of insomnia and to their consequences on social and cognitive functioning. They are now integrated in the definition of insomnia and are used to quantify its severity. If the daytime consequences of insomnia are well known at the clinical level, there are few epidemiological data on this matter. The aim of this study was to assess the daytime repercussions of insomnia complaints in the general population of France. A representative sample (n=5,622) aged 15 or older was surveyed by telephone with the help of the sleep-EVAL expert system, a computer program specially designed to evaluate sleep disorders and to manage epidemiological investigations. Interviews have been completed for 80.8% of the solicited subjects (n=5,622). The variables considered comprised insomnia and its daytime repercussions on cognitive functioning, affective tone, daytime sleepiness and diurnal fatigue. Insomnia was found in 18.6% of the sample. The prevalence was higher in women (22.4%) than in men (14.5%, p<0.001) with a relative risk of 1.7 (95% confidence interval 1.5 to 2) and was twice more frequent for subjects 65 years of age or older compared to subjects younger than 45 years. Approximately 30% of subjects reporting insomnia had difficulties initiating sleep. Nearly 75% of insomnia complainers reported having a disrupted sleep or waking up too early in the morning and about 40% said they had a non-restorative sleep. Repercussions on daytime functioning were reported by most insomnia subjects (67%). Repercussions on cognitive functioning changed according age, number of insomnia symptoms and the use of a psychotropic medication. A decreased efficiency was more likely to be reported by subjects between 15 and 44 years of age (OR: 2.9), those using a psychotropic (OR: 1.5), those reporting at least three insomnia symptoms (OR: 1.4) and women (OR: 1.4). The highest probability of the appearance of concentration difficulties was found in subjects younger than 65 Years, having a depressive disorder and using a psychotropic (15-44 years: OR 19.1; 45-64 years: OR 46.6). Difficulties maintaining attention were 15 times higher in subjects aged between 45 and 64 who were using a psychotropic and had also a depressive disorder. Memory difficulties were three times more likely to be reported by subjects using a psychotropic. At the affective level, irritability was 10 times more likely to be reported by subjects younger than 65 Years who were also using a psychotropic and had a depressive disorder. Independent of the presence of a mental disorder and the use of a psychotropic, subjects between 15 and 44 Years were five times more likely to be irritable following a bad sleep. Feeling depressed after a bad night's sleep was 18 times more likely to occur in subjects aged between 45 and 64 who were using a psychotropic and had a depressive disorder. Feeling anxious after a bad night's sleep was seven times more likely to occur in subjects with a depressive disorder. Daytime sleepiness was reported by approximately 20% of insomnia subjects. This rate was relatively comparable among gender, age groups, presence/absence of a mental disorder and use or not of a psychotropic. However, taking into account the interaction between age, use of a psychotropic and the presence of a mental disorder, subjects younger than 65 years, using a psychotropic and having a depressive disorder were at least 10 times more likely to report daytime sleepiness. Subjects who were suffering the most diurnal symptoms of insomnia were those younger than 65 years. Several factors can be evoked to explain this fact. These subjects were, for the most part, likelier to have a stricter sleep/wake schedule because of constraints imposed by work, studies, child care, etc. Subjects older than 65 Years were generally retired and therefore less prone to sleepiness and to cognitive difficulties. Insomnia consequences were limited due to their inactivity. Complementary studies should be undertaken to describe the daytime repercussions of insomnia for this specific age group of the general population and to measure these repercussions.

Abstract

To present sleep patterns in elderly individuals and factors associated with short sleep and long daytime and nighttime sleep.A total of 8091 subjects aged between 55 and 101 years representative of the noninstitutionalized general population of seven European countries (France, Finland, Italy, Germany, Portugal, Spain, and UK) were interviewed by telephone about their sleep habits and sleep disorders.The average sleep duration was 6 h and 57 min. Sleep duration was longer in men than in women. Five percent of the sample slept 5 h or less and 5% slept 9 h or more per night. Factors associated with short sleep (lower fifth percentile) were age, living in UK, no physical exercise, drinking six cups of coffee or more per day, taking a medication for sleep, difficulty initiating sleep, disrupted sleep, early morning awakening, and presence of an anxiety disorder. Factors associated with long sleep (> or =95th percentile) were age, living in France, Portugal, or Spain, being underweight, no physical exercise, disrupted sleep, taking a medication for sleep, and presence of an anxiety disorder. Long daytime sleep (54 min or more) were age, being a man, being overweight or obese, physical disease, being dissatisfied with one's social life, smoking, drinking alcohol, and having a major depressive disorder.Sleep patterns considerably varied among the countries in the elderly population. Extreme values of sleep duration (short and long sleep) were associated with several sleep and mental health problems.

Abstract

We studied the sleep of patients with insomnia during continuous and very long-term use of benzodiazepines (BZDs), and after withdrawal. A group of 25 patients (mean age 44.3+/-11.8 years) with persistent insomnia, who had been taking BZDs nightly for 6.8+/-5.4 years was selected. The control group was comprised of 18 age-matched healthy individuals. Sleep stage parameters were analyzed during Night 1 (while taking BZDs), Night 2 (first night after completing BZD withdrawal), and Night 3 (15 days after gradual BZD withdrawal). Sleep data for control subjects was monitored in parallel. Sleep EEGs of the patients were analyzed using Period Amplitude Analysis (PAA), during Nights 1 and 3 only. During BZD use, a significant reduction of Total Sleep Time (TST) and increased sleep latency were found in the insomniac group when compared to controls. We found an increase in stage 2 non-REM (NREM) sleep, and a reduction in Slow Wave Sleep (SWS) when comparing to night 3 (after withdrawal). Sleep EEGs analysis showed an increase in sigma band and decrease in delta count in stages 2, 3, 4 NREM and REM sleep in the BZD group when comparing to night 3 (after withdrawal). During the BZD withdrawal period, six out of nine subjects taking lorazepam failed withdrawal. In the remaining 19 subjects, gradual withdrawal of BZDs was associated with immediate worsening of nocturnal sleep, as indicated by sleep parameters. However, 15 days after withdrawal (Night 3), some of the sleep structure parameters of patients were not significantly different from baseline (while taking BZDs), except for a significant increase in SWS and in delta count throughout most sleep stages, and a decrease in stage 2 NREM sleep. These values were not different from those shown by control subjects. REM sleep parameters showed no significant variation across the experimental conditions. Subjective sleep quality was significantly improved on Night 3 compared with Night 1. Conclusions: Chronic intake of BZDs may be associated with poor sleep in this population. A progressive 15-day withdrawal did not avoid an immediate worsening of sleep parameters. But at the end of the protocol, SWS, delta count, and sleep quality were improved compared to those recorded during the chronic BZD intake, despite the lack of change in sleep efficiency.

Abstract

Several epidemiological surveys performed in Western Europe reported a prevalence of insomnia symptoms between 20% and 40% of the general population. Women and elderly individuals were the most affected. Many events can occur during sleep and affect its quality. Daytime sleepiness, a consequence of lack of sleep and/or insomnia, is responsible for many road, work and domestic accidents. Therefore, insomnia may have important consequences both for individuals and society. This study performed in the non institutionalized French population reports the sleep habits of that population and the factors associated with insomnia. This epidemiological study was conducted with 5,622 subjects representative of the French general population. They were aged between 15 and 96 Years. The participation rate was 80.8%. The results showed that men and women have different sleep habits. Generally speaking, women went to bed about 12 minutes earlier than men and woke up later than men (p<0.001). Women also took more time to fall asleep than men but only when they were aged between 35 and 65 Years. Furthermore, women had a longer sleep than men except between the ages of 55 and 74, where men slept significantly more than women. However, sleep efficiency was lower in women than in men who were over age 35. This was due to a greater frequency of nocturnal awakenings in women than in men. Sleep habits also changed with age: Bedtime became progressively earlier with advancing age and wake-up time was later when the subjects reached retirement age. Sleep latency progressively increased with age after 35. Similarly, disrupted sleep increased with age and was reported by more than half of subjects 75 years or older. We found also that evening or night workers showed irregularities in their sleep patterns: sleep latency was significantly longer - at least 12 minutes - compared to daytime and shift workers (p<0.001). They also had a shorter sleep duration of about 30 minutes compared to shift workers, and 40 minutes compared to daytime workers (p<0.001). Shift workers and evening or night workers had a lower sleep efficiency compared to daytime workers. Finally, in regions with greater density population (>100,000 inhabitants) sleep duration was shorter by approximately 10 minutes compared to localities with fewer than 5,000 residents (p<0.01). Similarly, bedtime and wake up hours were more related in regions with more than 100,000 inhabitants compared to small localities (fewer than 5,000 residents). Insomnia complaints, defined as the presence of at least one insomnia symptom accompanied by sleep dissatisfaction or use of a sleep medication, were reported by 18.6% of the sample. The prevalence was higher in women (22.4%) than in men (14.5%) and increased with age. However, the proportion of subjects dissatisfied with their sleep remained comparable for all age groups; it was the number of subjects using a sleep medication that increased with age. This was 3.2% in subjects 44 years or younger, 13.3% in subjects between 45 and 64 years, 22% of those between 65 and 74 years and almost a third of individuals 75 Years or older (32%; p<0.001). However, insomnia symptoms remained present for most of these consumers: 80.4% of those between 15 and 44 years, 87.9% of those between 45 and 64 Years, 81.4% of those between 65 and 74 years and 78.8% of subjects of 75 years or older. Compared to subjects in other epidemiological studies undertaken in England, Germany and Italy and using the same methodology, subjects in this study complained with their sleep more often. Insufficient sleep was found more often in the active population, which is subject to schedule constraints. Shift workers as well as evening or night workers were the most likely to have a sleep debt.

Prevalence and risk factors of morning headaches in the general populationARCHIVES OF INTERNAL MEDICINEOhayon, M. M.2004; 164 (1): 97-102

Abstract

To determine the prevalence of chronic morning headaches (CMH) in the general population and their relationship to sociodemographic characteristics, psychoactive substance use, and organic, sleep, and mental disorders.A telephone questionnaire was submitted to 18 980 individuals 15 years or older and representative of the general populations of the United Kingdom, Germany, Italy, Portugal, and Spain. It included a series of questions about morning headaches, organic disorders, use of psychoactive substances, and sleep and mental disorders in accordance with the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV).Overall, the prevalence of CMH was 7.6% (n = 1442); CMH were reported to occur "daily" by 1.3% of the sample, "often" by 4.4%, and "sometimes" by 1.9%. Rates were higher in women than in men (8.4% vs 6.7%) and in subjects aged between 45 and 64 years (about 9%). The median duration for CMH was 42 months. Various conditions and disorders were found positively associated with CMH. The most significant associated factors were comorbid anxiety and depressive disorders (28.5% vs 5.5%), major depressive disorder alone (21.3% vs 5.5%), dyssomnia not otherwise specified (17.1% vs 6.9%), insomnia disorder (14.4% vs 6.9%), and circadian rhythm disorder (20.0% vs 7.5%). Sleep-related breathing disorder (15.2% vs 7.5%), hypertension (11.0% vs 7.2%), musculoskeletal diseases (14.1% vs 7.1%), use of anxiolytic medication (20.1% vs 7.3%), and heavy alcohol consumption (12.6% vs 7.7%) were also significantly associated with CMH.Morning headache affects 1 individual in 13 in the general population. Chronic morning headaches are a good indicator of major depressive disorders and insomnia disorders. Contrary to what was previously suggested, however, they are not specific to sleep-related breathing disorder.

Specific characteristics of the pain/depression association in the general populationJOURNAL OF CLINICAL PSYCHIATRYOhayon, M. M.2004; 65: 5-9

Abstract

To evaluate how the presence of a chronic painful physical condition (CPPC) lasting 6 months or more influences the frequency and severity of depressive symptoms in subjects with major depressive disorder (MDD).Random samples of 18,980 subjects aged between 15 and 100 years who were representative of the general population of 5 European countries (the United Kingdom, Germany, Italy, Portugal, and Spain) were interviewed by telephone between 1994 and 1999. Subjects answered a series of questions that allowed positive and differential diagnosis of DSM-IV mental disorders. The questionnaire also included a series of questions about painful physical conditions, medical treatment, consultations, and hospitalizations for medical conditions and a list of diseases.A total of 4% (95% CI = 3.7% to 4.3%) of the sample had MDD at the time of the interview. Nearly half of subjects with MDD (43.4%) also reported having a CPPC. Compared with MDD subjects without chronic pain, MDD subjects with a CPPC had a longer duration of depressive symptoms (7 months longer) and were more likely to report severe fatigue (OR = 5.4), insomnia nearly every night (OR = 3.3), severe psychomotor retardation (OR = 3.3), weight gain (OR = 2.3), severe difficulty concentrating (OR = 1.7), and severe feelings of sadness or depressed mood (OR = 1.8).A CPPC was present in nearly half of subjects with MDD. CPPCs increased the severity of physical symptoms of depression (fatigue, insomnia, psychomotor retardation, weight gain). Moreover, CPPCs affected the duration of depressive episodes and their recurrence. Physicians should consider CPPCs as a major factor in the expression and evolution of MDD. They must remember that MDD patients tend to amplify physical symptoms, to the detriment of their depressive symptomatology.

The effects of breathing-related sleep disorders on mood disturbances in the general populationJOURNAL OF CLINICAL PSYCHIATRYOhayon, M. M.2003; 64 (10): 1195-1200

Abstract

Results of clinical studies suggest that there may be a relationship between breathing-related sleep disorders and depressive disorders. This study aims to assess the impact of breathing-related sleep disorder on major depressive disorder in the general population.A cross-sectional telephone survey was carried out between 1994 and 1999 in the general population of the United Kingdom, Germany, Italy, Portugal, and Spain. A total of 18,980 randomly selected subjects aged 15 to 100 years and representative of the general population of their respective countries participated in the study. The questionnaire included a series of questions about sleep quality, breathing-related sleep disorder symptoms, mental disorders, and medical conditions. Data are presented using point prevalence.2.1% of the subjects were found with obstructive sleep apnea syndrome at the time of the interview, and 2.5% had some other type of DSM-IV breathing-related sleep disorder diagnosis. The association of DSM-IV breathing-related sleep disorder diagnosis and major depressive disorder diagnosis was found in 0.8% of the sample. As many as 18% of individuals with a major depressive disorder diagnosis also have a DSM-IV breathing-related sleep disorders diagnosis, and 17.6% of subjects with a DSM-IV breathing-related sleep disorders diagnosis have a major depressive disorder diagnosis. Multivariate models showed that even after controlling for obesity and hypertension, the odds of having a DSM-IV breathing-related sleep disorders diagnosis was 5.26 for individuals with a major depressive disorder diagnosis.About 800 of 100,000 individuals have both a breathing-related sleep disorder and a major depressive disorder. The identification of 1 of these 2 disorders should prompt the investigation of the other disorder since nearly a fifth of them have the other disorder.

Using chronic pain to predict depressive morbidity in the general populationARCHIVES OF GENERAL PSYCHIATRYOhayon, M. M., Schatzberg, A. F.2003; 60 (1): 39-47

Abstract

Pain syndrome is thought to play a role in depression. This study assesses the prevalence of chronic (>or= 6 months' duration) painful physical conditions (CPPCs) (joint/articular, limb, or back pain, headaches, or gastrointestinal diseases) and their relationship with major depressive disorder.We conducted a cross-sectional telephone survey of a random sample of 18 980 subjects from 15 to 100 years old representative of the general populations of the United Kingdom, Germany, Italy, Portugal, and Spain. Answers provided during telephone interviews using the Sleep-EVAL system were the main outcome measure. Interviews included questions about mental disorders and medical conditions. Data on painful physical conditions were obtained through questions about medical treatment, consultations, and/or hospitalizations for medical conditions and a list of 42 diseases.Of all subjects interviewed, 17.1% reported having at least 1 CPPC (95% confidence interval [CI], 16.5%-17.6%). At least 1 depressive symptom (sadness, depression, hopelessness, loss of interest, or lack of pleasure) was present in 16.5% of subjects (95% CI, 16.0%-17.1%); 27.6% of these subjects had at least 1 CPPC. Major depressive disorder was diagnosed in 4.0% of subjects; 43.4% of these subjects had at least 1 CPPC, which was 4 times more often than in subjects without major depressive disorder (odds ratio [OR], 4.0; 95% CI, 3.5-4.7). In a logistic regression model, CPPC was strongly associated with major depressive disorder (OR: CPPC alone, 3.6; CPPC + nonpainful medical condition, 5.2); 24-hour presence of pain made an independent contribution to major depressive disorder diagnosis (OR, 1.6).The presence of CPPCs increases the duration of depressive mood. Patients seeking consultation for a CPPC should be systematically evaluated for depression.

Place of chronic insomnia in the course of depressive and anxiety disordersJOURNAL OF PSYCHIATRIC RESEARCHOhayon, M. M., Roth, T.2003; 37 (1): 9-15

Abstract

Insomnia is frequent in the general population and is often related to a psychiatric illness. However, little is known about how the chronicity of insomnia affects this relation and how often subjects with chronic insomnia have antecedents of psychiatric disorders.A total of 14,915 subjects aged from 15 to 100 years representative of the general population of the United Kingdom, Germany, Italy, and Portugal were interviewed by telephone using the Sleep-EVAL system. The questionnaire assessed current psychiatric disorders according to the DSM-IV classification and a series of questions assessed the psychiatric history. Insomnia was considered as chronic when it lasted for 6 months or more.The prevalence for insomnia accompanied with impaired daytime functioning was 19.1% and significantly increased with age. More than 90% of these subjects had a chronic insomnia. About 28% of subjects with insomnia had a current diagnosis of mental disorders and 25.6% had a psychiatric history. A DSM-IV insomnia disorder was found in 6.6% of the sample. Presence of severe insomnia, diagnosis of primary insomnia or insomnia related to a medical condition, and insomnia that lasted more than one year were predictors of a psychiatric history. In most cases of mood disorders, insomnia appeared before (> 40%) or in the same time (> 22%) than mood disorder symptoms. When anxiety disorders were involved, insomnia appeared mostly in the same time (>38%) or after (> 34%) the anxiety disorder.The study shows that psychiatric history is closely related to the severity and chronicity of current insomnia. Moreover, chronic insomnia can be a residual symptom of a previous mental disorder and put these subjects to a higher risk of relapse.

Abstract

The purpose of this study is to assess the prevalence of insomnia symptoms and diagnoses in the general population of Finland. A total of 982 participants, aged 18 years or older and representative of the general population of Finland, were interviewed by telephone using the Sleep-EVAL system. The participation rate was 78%. The questionnaire included the assessment of sleep habits, insomnia symptomatology according to Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) and International Classification of Sleep Disorders (ICSD), associated and sleep/mental disorders and daytime consequences. The overall prevalence of insomnia symptoms occurring at least three nights per week was 37.6%. Difficulty initiating sleep were mentioned by 11.9% of the sample, difficulty maintaining sleep by 31.6%, early morning awakenings by 11.0% and non-restorative sleep by 7.9% of the sample. Global dissatisfaction with sleep was found in 11.9% of the sample. Daytime consequences (fatigue, mood changes, cognitive difficulties or daytime sleepiness) were reported by 39.9% of participants with insomnia symptoms and 87.6% of those with sleep dissatisfaction. A deterioration of sleep in summer or winter was associated with more complaints of sleep dissatisfaction. Prevalence of any DSM-IV insomnia diagnosis was 11.7%. More specifically, DSM-IV diagnosis of primary insomnia had a prevalence of 1.6% and DSM-IV diagnosis of insomnia related to another mental disorder was at 2.1%. Insomnia was a symptom of another sleep disorder in about 16% of cases and of a mental disorder in about 17% of cases. As reported in other Nordic studies, sleep quality was worse in summer. Insomnia symptomatology was common and was reported by more than a third of Finnish participants. Compared with other European countries studied with the same methodology (France, the UK, Germany, and Italy), the prevalence of DSM-IV insomnia diagnosis was 1.5 to two times higher in Finland.

Prevalence of depressive episodes with psychotic features in the general populationAMERICAN JOURNAL OF PSYCHIATRYOhayon, M. M., Schatzberg, A. F.2002; 159 (11): 1855-1861

Abstract

The study evaluated the prevalence of major depressive episodes with psychotic features in the general population and sought to determine which depressive symptoms are most frequently associated with psychotic features.The sample was composed of 18,980 subjects aged 15-100 years who were representative of the general populations of the United Kingdom, Germany, Italy, Portugal, and Spain. The participants were interviewed by telephone by using the Sleep-EVAL system. The questionnaire included a series of questions about depressive disorders, delusions, and hallucinations.Overall, 16.5% of the sample reported at least one depressive symptom at the time of the interview. Among these subjects, 12.5% had either delusions or hallucinations. More than 10% of the subjects who reported feelings of worthlessness or guilt and suicidal thoughts also had delusions. Feelings of worthlessness or guilt were also associated with high rates of hallucinations (9.7%) and combinations of hallucinations and delusions (4.5%). The current prevalence of major depressive episode with psychotic features was 0.4% (95% CI=0.35%-0.54%), and the prevalence of a current major depressive episode without psychotic features was 2.0% (95% CI=1.9%-2.1%), with higher rates in women than in men. In all, 18.5% of the subjects who fulfilled the criteria for a major depressive episode had psychotic features. Past consultations for treatment of depression were more common in depressed subjects with psychotic features than in depressed subjects with no psychotic features.Major depressive episodes with psychotic features are relatively frequent in the general population, affecting four of 1,000 individuals. Feelings of worthlessness or guilt can be a good indicator of the presence of psychotic features.

Abstract

Upper airway resistance syndrome (UARS) and obstructive sleep apnea syndrome (OSAS) are associated with arousals and autonomic activation. Pulse transit time (PTT) has been used to recognize transient arousals. We examined the accuracy of PTT to recognize arousals, and the relationship between PTT deflection and visual and non-visual arousals.Ten UARS and 10 mild OSAS subjects were studied via polysomnography including measurement of esophageal pressure. Electroencephalogram (EEG) spectral power was obtained from central leads. Seven types of events were identified, depending upon the presence or absence of: a sleep-related respiratory event (SRRE), i.e. apnea, hypopnea, and abnormal breathing effort; a PTT signal; or a visually scored arousal (>1.5s).One thousand four hundred forty-six events were identified in 20 subjects. Fifty-nine percent of all SRREs were associated with a PTT signal and a visual EEG arousal. Nineteen percent of SRREs had no EEG arousals at their termination, and 7.4% had no associated PTT signal. Delta power was significantly increased when non-visual EEG arousals were scored. The time delay for PTT was determined by the presence or absence of EEG arousal. The sensitivity of PTT to recognize EEG arousal was 90.4% and the specificity was 16.8%. The sensitivity and specificity of PTT to recognize SRRE was 90.7 and 21.9%, respectively.These results preclude the use of PTT by itself. SRREs induce an activation with positive PTT response but without arousal in 14% of cases. This PTT response, however, is much slower than that occurring with arousal. UARS and mild OSAS do not respond in the same way to SRREs, particularly during rapid eye movement sleep.

[A connection between insomnia and psychiatric disorders in the French general population].L'Ence´phaleOhayon, M. M., Lemoine, P.2002; 28 (5): 420-428

Abstract

Untreated insomnia often has repercussions on socio-professional or cognitive functioning of insomniacs. In industrialized countries, the prevalence of insomnia ranges between 10% and 48%, depending on the methodology and the measured time interval. However, few studies have examined the relationship between insomnia and mental disorder diagnoses. This epidemiological study on insomnia complaints was conducted on 5 622 subjects representative of the non-institutionalized French population aged 15 years or over. Sixteen interviewers using the Sleep-EVAL expert system performed telephone interviews. Insomnia complaints (defined as difficulty initiating or maintaining sleep, feeling unrefreshed at awakening accompanied by dissatisfaction with sleep quality or quantity, or use of sleep-promoting medication) were observed in 18.6% (95% confidence interval: 17.6% to 19.6%) of the sample. The median duration of insomnia complaints was five years. Regional variations in the prevalence of insomnia complaints were observed in France. In North 2 and Center 4 regions, the prevalence of insomnia complaints was higher compared to the rest of France with a relative risk of 1.4 (95% confidence interval: 1.1-1.6) time superior for the North region and 1.3 (95% CI: 1.0-1.6) for the Center 4 region. The lowest prevalence was registered in the Mediterranean area. In most regions, the prevalence of insomnia complaints was higher in women than in men with the exception of the South and West regions where the prevalence was similar. Subjects with insomnia complaints consulted more frequently compared to the rest of sample with an odds ratio of 3 to 1 [95% CI: 2.8 to 4.1]. Close to 20% of subjects were being treated for a physical disease at the time of the survey; subjects with insomnia complaints being twice more numerous (34.3%) than the rest of the sample (15.9%; p<0.001). To identify the main factors associated with insomnia complaints, socio-demographic and health variables were introduced in a multivariate model. Separated or divorced individuals (OR: 1.6); widowers (OR: 1.5); subjects aged between 45 and 65 years (OR: 1.4) or older than 65 (OR: 1.5); women (OR: 1.3); those with little or no education (OR: 1.4); and subjects living in the North region had higher reported insomnia complaints. Living in the East region (Mediterranean) was a protective factor (OR: 0.6). Furthermore, subjects with vascular diseases (OR: 2.0), musculo-skeletal diseases (OR: 2.0) or cardiac diseases (OR: 1.9) and those who had consulted a physician in the previous six months (OR: 2.7) had higher a probability of insomnia complaints. Subsequently, DSM IV insomnia diagnoses were examined in subjects who complained of insomnia. A diagnosis of primary insomnia was found in 7% of these subjects. A diagnosis of insomnia related to another mental disorder was found in 15.6% of insomnia complainers. A depressive disorder diagnosis was given in 10.8% of cases (mainly a major depressive disorder). This diagnosis was made more often among women and subjects of less than 65 years. An anxiety disorder diagnosis was given for 33.1% of insomnia complainers (an anxiety generalized disorder in about half the cases). About a quarter of insomnia complainers did not receive a diagnosis. This was the case more often for men and the subjects 65 years or older. If demographic and medical factors are relatively well documented at the epidemiological level, it is otherwise for psychiatric diagnosis associated with insomnia complaint. Very few studies in the general population have been done and still fewer of them have applied a positive and differential diagnosis process. In this study, we used the DSM IV classification to establish positive and differential diagnoses among subjects with insomnia complaints. Compared to other epidemiological studies, our study is distinguished by several aspects: 1) insomnia complaint had a narrower definition. It did not suffice that the subject reported insomnia symptoms, it was also necessary that the subject said s/he was dissatisfied with her/hr/his sleep or that s/he took measures to improve it (medication or sleep hygiene). This choice was motivated essentially by the fact that it is difficult, from a point of clinical point of view, to consider that an individual has insomnia solely based on the presence of symptoms, that, appreciated by a clinician, would resemble insomnia without that they make problem for the subject. 2) Several sleep habits were systematically collected. The majority of epidemiological studies are not centered on sleep problems, with the consequence that results do not allow a global view of factors that are associated with insomnia. 3) The various diagnostic categories of insomnia as well as elements of the differential diagnosis were applied. Thus, we can conclude that insomnia, as a diagnostic entity, including all its forms, is found in 5.6% of the French population. In the majority of cases, the insomnia complaint is part of the symptomatology of a mental disorder, mainly an anxiety disorder. This distinction is important since it helps the physician to determine therapeutic choices. To conclude, it is worthwhile to consider the number of insomnia complainers who had consulted a physician, mainly a general practitioner, in the six months prior to the study. This designates physicians as the first-line resource in the treatment and the prevention of sleep disorders.

Use of psychotropic medication in the general population of France, Germany, Italy, and the United KingdomJOURNAL OF CLINICAL PSYCHIATRYOhayon, M. M., Lader, M. H.2002; 63 (9): 817-825

Abstract

The use of psychotropic medications and its association with sleep and psychiatric and physical illnesses were studied in the general population.A cross-sectional telephone survey was carried out using the Sleep-EVAL knowledge-base system. A representative sample of the noninstitutionalized general populations of France, Germany, Italy, and the United Kingdom, aged 15 years or over, was interviewed (N = 18,679; participation rate: 78.8%; target population: 204,605,391 inhabitants). Questions were asked about psychotropic medication intake (name of medication, indication, dosage, duration of intake, prescriber), sociodemographics, physical illnesses, and DSM-IV mental disorders.At the time of the interview, 6.4% of the subjects took a psychotropic medication. Anxiolytics were reported by 4.3% of the sample, hypnotics by 1.5%, antidepressants by 1.0%, and neuroleptics and other psychotropics by less than 1.0%. Hypnotics and anxiolytics were mostly used as a sleep disorder treatment. Antidepressants were taken appropriately for a depressive illness in only 44.1% of cases. Low doses of hypnotics and anxiolytics were found in about 10% of cases and low doses of antidepressants in 31.7% of cases. Subjects with a psychiatric disorder received a psychotropic treatment only infrequently (between 10% to 40.4%, depending on the disorder). All psychiatric disorders, including mood disorders, were treated mainly with an anxiolytic. A concomitant physical illness increased the likelihood of using a psychotropic treatment and was a strong predictor of adequate psychotropic dosage.Psychiatric pathology and sleep disorders remained mostly untreated or inadequately managed in the general population. Depression is underdiagnosed by the physicians and is treated with antidepressant in only 7% of cases. By contrast, anxiolytics are extensively prescribed, especially in France and Italy. The co-occurrence of organic and psychiatry disorders increases the frequency of medical consultations and the likelihood of being given a prescription for the mental disorder.

Abstract

Periodic limb movement disorder (PLMD) and restless legs syndrome (RLS) are two sleep disorders characterized by abnormal leg movements and are responsible for deterioration in sleep quality. However, the prevalence of these disorders is not well known in the general population. This study aims to document the prevalence of RLS and PLMD in the general population and to identify factors associated with these conditions.Cross-sectional studies were performed in the UK, Germany, Italy, Portugal and Spain. Overall, 18,980 subjects aged 15 to 100 years old representative of the general population of these five European countries underwent telephone interviews with the Sleep-EVAL system. A section of the questionnaire assessed leg symptoms during sleep. The diagnoses of PLMD and RLS were based on the minimal criteria provided by the International Classification of Sleep Disorders.The prevalence of PLMD was 3.9% and RLS was 5.5%. RLS and PLMD were higher in women than in men. The prevalence of RLS significantly increased with age. In multivariate models, being a woman, the presence of musculoskeletal disease, heart disease, obstructive sleep apnea syndrome, cataplexy, doing physical activities close to bedtime and the presence of a mental disorder were significantly associated with both disorders. Factors specific to PLMD were: being a shift or night worker, snoring, daily coffee intake, use of hypnotics and stress. Factors solely associated with RLS were: advanced age, obesity, hypertension, loud snoring, drinking at least three alcoholic beverages per day, smoking more than 20 cigarettes per day and use of SSRI.PLMD and RLS are prevalent in the general population. Both conditions are associated with several physical and mental disorders and may negatively impact sleep. Greater recognition of these sleep disorders is needed.

Abstract

In Western countries, insomnia is associated with daytime impaired functioning, as well as physical and psychiatric illnesses. However, little information exists on insomnia in Asian countries. This study investigates the prevalence and correlates of insomnia in the general population of South Korea.A representative sample of the South Korean general population composed of 3719 noninstitutionalized individuals aged 15 years or older were interviewed by telephone using the Sleep-EVAL system. The participation rate was 91.4%. The interviews covered sleep habits, sleep symptomatology, physical and psychiatric illnesses. DSM-IV sleep and psychiatric disorder diagnoses were also assessed.Insomnia symptoms occurring at least three nights per week were reported by 17.0% of the sample; difficulty initiating sleep (DIS) was mentioned by 4.0% of the sample, difficulty maintaining sleep (DMS) by 11.5%, early morning awakenings (EMA) by 1.8%, and nonrestorative sleep (NRS) by 4.7% of the sample. DSM-IV insomnia disorder diagnoses were found in 5% of the sample. Over 50% of subjects with insomnia symptoms reported important daytime consequences and another 20% reported mild or moderate consequences. However, the proportion of insomnia subjects seeking medical help for their sleep problems was very low (6.8%).As in Western countries, insomnia is widespread in South Korea, affecting nearly one in five individuals. Many of them would benefit from medical help; however, few insomnia subjects are consulting for this problem. An educational effort is needed for both the general population and the physicians.

Abstract

Irregular work schedules often results in a disruption of the normal circadian rhythm that can causes sleepiness when wakefulness is required and insomnia during the main sleep episode.Two physicians using the Sleep-EVAL system interviewed 817 staff members of a psychiatric hospital. The interviews were done during the working hours. In addition to a series of questions to evaluate sleep and mental disorders, the evaluation included a standard questionnaire assessing work conditions, work schedule and their consequences. Three work schedules were assessed: (1) fixed daytime schedule (n=442), (2) rotating daytime shifts (n=323) and (3) shift or nighttime work (n=52).Subjects working on rotating daytime shifts were younger than the two other groups and had a higher proportion of women. Participants working on rotating daytime shifts reported more frequently than the fixed daytime schedule workers to have difficulty initiating sleep (20.1% vs. 12.0%). The sleep duration of shift or nighttime workers was shorter than that of the two other groups. Furthermore, subjects working rotating daytime schedule reported to have shorter sleep duration of about 20 min when they are assigned to the morning shift. Work-related accidents were two times more frequent among the rotating daytime workers (19.5%) compared with the fixed daytime schedule workers (8.8%) and the group of nighttime or shift workers (9.6%). Sick leaves in the previous 12 months were also more frequently reported in the rotating daytime schedule group (62.8%) as compared with the daytime group (38.5%, P

Abstract

To determine the prevalence of narcolepsy in the general population of five European countries (target population 205,890,882 inhabitants).Overall, 18,980 randomly selected subjects were interviewed (participation rate 80.4%). These subjects were representative of the general population of the UK, Germany, Italy, Portugal, and Spain. They were interviewed by telephone using the Sleep-EVAL expert system, which provided narcolepsy diagnosis according to the International Classification of Sleep Disorders (ICSD).Excessive daytime sleepiness was reported by 15% of the sample, with a higher prevalence in the UK and Germany. Napping two times or more in the same day was reported by 1.6% of the sample, with a significantly higher rate in Germany. Cataplexy (episodes of loss of muscle function related to a strong emotion), a cardinal symptom of narcolepsy, was found in 1.6% of the sample. An ICSD narcolepsy diagnosis was found in 0.047% of the sample: The narcolepsy was severe for 0.026% of the sample and moderate in 0.021%.This is the first epidemiologic study that estimates the prevalence of narcolepsy in the general population of these five European countries. The disorder affects 47 individuals/100,000 inhabitants.

Methodology of a study on insomnia in the general populationENCEPHALE-REVUE DE PSYCHIATRIE CLINIQUE BIOLOGIQUE ET THERAPEUTIQUEOhayon, M. M.2002; 28 (3): 217-226

Abstract

The study of sleep disorders in the general population involves several methodological issues that need to be defined prior to proceeding to the epidemiological study. The rigor of the methodology is an important issue since it will determine the reliability of the data gathered. This paper describes the methodology used in an epidemiological study performed in the French general population using telephone interviews with the help of Sleep-EVAL, an expert system designed for this purpose. The study aimed to investigate the prevalence of insomnia disorders according to the DSM IV classification and the use of psychotropic medications in the general population. The methodological choices for this study were based on several considerations. First, the sample had to be representative of the French population. Second, the study had to be conducted in the shortest period of time. Third, the interviews had to be conducted with respect to a strict standardization and fourth, the realization costs had to be minimal for a maximum of data collected. The telephone interview procedure was chosen over postal and face-to-face interviews because it offered the possibility of conducting all the interviews from the same site. Supervision was easier. It also offered an absolute control in the application of the selection procedure. To draw the sample, a two-stage procedure was adopted. At the first stage, we pulled a random series of telephone numbers in each Nielsen region with respect to the size of the settlement. At the second stage, during the initial telephone contact, a household member was chosen using the Kish selection procedure. This method is based on the utilization of eight tables of selection that allows for the choice of the person to interview in a given household and keeps the representativeness of the sample. This technique is little used in telephone surveys because of its burden and its intrusive nature: the interviewer must collect the age and gender of all eligible subjects, to classify men from the oldest to youngest and then to classify women. However, it is the most rigorous selection method for epidemiological surveys. To reduce the refusal rates and to alleviate the work of interviewers, the Kish method was implanted in the computer software used for this study. For this study, the exclusion criteria were minimal. Only individuals younger than 15 years of age, those with a speech or hearing impairment and those who were too ill to perform the interview were not included. Subjects who refused to participate, those who hung up without speaking to the interviewer and those who hung up before completing at least half of the interview were tabulated as refusal. The participation rate was calculated by dividing the number of completed interviews by the number of eligible participants (completed interviews, refusals and telephone numbers where the interviewer was unable to determine if the individuals met an exclusion criterion). In this study, the participation rate was 80.8% (5 622 completed interviews/6 966 eligible households). The diagnostic tool used for this study was the Sleep-EVAL system, an expert system designed to conduct epidemiological studies in the general population. It is a level 2, non-monotonic system endowed with a causal reasoning able to provide sleep and mental disorders diagnoses according to the DSM IV classification for this study. Subsequent versions of Sleep-EVAL also included the International Classification of Sleep Disorders. System symbolic representation of the classifications was put in a compiled knowledge base. This knowledge base was read and interpreted by the inference engine at the beginning of the interview. During the interview, this interpretation changed as a function of the answers provided by the interviewee and by deductions made from the analysis of information the system already knew. All interviews began with a standard questionnaire about sociodemographic information and sleep habits. From these first answers, the Sleep-EVAL system emitted a series of diagnostic hypotheses that were confirmed or rejected with supplementary questions. The interview ended once all diagnostic possibilities were exhausted. The validity of the Sleep-EVAL system was demonstrated in different studies performed in sleep disorders clinics. There were several advantages in using such a tool to conduct epidemiological surveys. No special skills from the interviewers nor specific knowledge of sleep and mental disorders were required. All the questions were chosen and formulated by the Sleep-EVAL system. The interviewer had simply to read the questions as they appeared on the monitor screen and enter the interviewee's responses by clicking the appropriate answer or typing it on the keyboard. Missing answers were non-existent because there was no possibility of skipping a question or entering inconsistent answers. It also ensured the uniformity of the interviews. Furthermore, it allowed the exploration of infrequent diagnoses. In summary, the methodology used for this study allowed for the investigation of the sleep pathology of the French population in a short period of time: only three months were necessary to complete the 5 622 interviews. The use of a computerized tool greatly facilitated the training of the interviewers and also their work. Furthermore, it ensured a standardized administration of the interviews and the exploration of a broad range of disorders that could hardly be realized with traditional paper-pencil questionnaires.

Abstract

The authors studied the sleep of patients with insomnia who complained of poor sleep despite chronic use of benzodiazepines (BZDs). The sample consisted of 19 patients (mean age 43.3+/-10.6 years) with primary insomnia (DSM-IV), who had taken BZDs nightly, for 7.1+/-5.4 years. The control group was composed of 18 healthy individuals (mean age 37+/-8 years). Sleep electroencephalogram (EEG) of the patients was analyzed with period amplitude analysis (PAA) and associated algorithms, during chronic BZD use (Night 1), and after 15 days of a valerian placebo trial (initiated after washout of BZD, Night 2). Sleep of control subjects was monitored in parallel.Valerian subjects reported significantly better subjective sleep quality than placebo ones, after BZD withdrawal, despite the presence of a few side effects. However, some of the differences found in sleep structure between Night 1 and Night 2 in both the valerian and placebo groups may be due to the sleep recovery process after BZD washout. Example of this are: the decrease in Sleep Stage 2 and in sigma count; the increase in slow-wave sleep (SWS), and delta count, which were found to be altered by BZD ingestion. There was a significant decrease in wake time after sleep onset (WASO) in valerian subjects when compared to placebo subjects; results were similar to normal controls. Nonetheless, valerian-treated patients also presented longer sleep latency and increased alpha count in SWS than control subjects.The decrease in WASO associated with the mild anxiolytic effect of valerian appeared to be the major contributor to subjective sleep quality improvement found after 2-week of treatment in insomniacs who had withdrawn from BDZs. Despite subjective improvement, sleep data showed that valerian did not produce faster sleep onset; the increase in alpha count compared with normal controls may point to residual hyperarousabilty, which is known to play a role in insomnia. Nonetheless, we lack data on the extent to which a sedative drug can improve alpha sleep EEG. Thus, the authors suggest that valerian had a positive effect on withdrawal from BDZ use.

Epidemiology of insomnia: what we know and what we still need to learnSLEEP MEDICINE REVIEWSOhayon, M. M.2002; 6 (2): 97-111

Abstract

Epidemiologists have published more than 50 studies of insomnia based on data collected in various representative community-dwelling samples or populations. These surveys provide estimates of the prevalence of insomnia according to four definitions: insomnia symptoms, insomnia symptoms with daytime consequences, sleep dissatisfaction and insomnia diagnoses. The first definition, based on insomnia criteria as defined by the DSM-IV, recognizes that about one-third of a general population presents at least one of them. The second definition shows that, when daytime consequences of insomnia are taken into account, the prevalence is between 9% and 15%. The third definition represents 8-18% of the general population. The last definition, more precise and corresponding to a decision-making diagnosis, sets the prevalence at 6% of insomnia diagnoses according to the DSM-IV classification. These four definitions of insomnia have higher prevalence rates in women than in men. The prevalence of insomnia symptoms generally increases with age, while the rates of sleep dissatisfaction and diagnoses have little variation with age. Numerous factors can initiate or maintain insomnia. Mental disorders and organic diseases are the factors that have been the most frequently studied. The association between insomnia and major depressive episodes has been constantly reported: individuals with insomnia are more likely to have a major depressive illness. Longitudinal studies have shown that the persistence of insomnia is associated with the appearance of a new depressive episode. Future epidemiological studies should focus on the natural evolution of insomnia. Epidemiological genetic links of insomnia are yet to be studied.

Prevalence and consequences of insomnia disorders in the general population of ItalySLEEP MEDICINEOhayon, M. M., Smirne, S.2002; 3 (2): 115-120

Abstract

To assess the prevalence of insomnia disorders using DSM-IV classification, and the consequences of insomnia in the Italian general population.A representative sample of the Italian general population composed of 3970 individuals aged 15 years or older were interviewed by telephone using the Sleep-EVAL system (participation rate: 89.4%). Participants were interviewed about their sleep habits and sleep disorders. DSM-IV classification was used by Sleep-EVAL to determine the sleep disorder diagnosis.Insomnia symptoms were reported by 27.6% of the sample. Sleep dissatisfaction was found in 10.1% and insomnia disorder diagnoses in 7% of the sample. The use of sleep-enhancing medication was reported by 5.7% of the sample. Most of these subjects were using anxiolytics. Dissatisfaction with sleep was associated with daytime sleepiness. Middle-aged drivers dissatisfied with their sleep were three times more likely to have had a road accident in the previous year compared to other drivers. However, fewer than 30% of subjects dissatisfied with their sleep or with an insomnia disorder diagnosis had consulted a physician about their sleep problem.As in other European and non-European countries, insomnia is widespread in Italy. The consequences are important. Appropriate recognition and treatment of insomnia should be part of an educational program for general practitioners everywhere.

Abstract

Recent findings suggest that there may be a relationship between excessive daytime sleepiness (EDS) and cognitive deficits. This study aims to determine to what extent EDS is predictive of cognitive impairment in an elderly population.A total of 1026 individuals 60 years or older representative of the general population living in the metropolitan area of Paris, France, were interviewed by telephone using the Sleep-EVAL expert system. To find these individuals, 7010 randomly selected households were called: 1269 had at least 1 household member in this age range (participation rate, 80.9%). In addition to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and International Classification of Sleep Disorders diagnoses, the system administered to participants the Psychological General Well-being Schedule, the Cognitive Difficulties Scale (MacNair-R), and an independent living scale.Excessive daytime sleepiness was reported by 13.6% of the sample, with no significant difference among age groups. Compared with nonsleepy participants, those with EDS were at increased risk of cognitive impairment on all the dimensions of the MacNair-R scale after controlling for age, sex, physical activity, occupation, organic diseases, use of sleep or anxiety medication, sleep duration, and psychological well-being. The odd ratios were 2.1 for attention-concentration deficits, 1.7 for praxis, 2.0 for delayed recall, 2.5 for difficulties in orientation for persons, 2.2 for difficulties in temporal orientation, and 1.8 for prospective memory.Among elderly individuals in the general population, EDS is an important risk factor for cognitive impairment. A complaint of EDS by an elderly patient should signal the possibility of an underlying cognitive impairment in need of evaluation.

Abstract

The use of diagnostic classifications to define sleep disorders is still unusual in epidemiological studies assessing the prevalence of sleep disorders in an adolescent population.Cross-sectional study. Representative samples of general populations in United Kingdom, Germany and Italy were selected and interviewed by telephone about their sleep habits, sleep and mental disorder diagnoses. Overall, 724 adolescents ages 15-18 years and 1447 young adults ages 19 to 24 years were interviewed. ICSD-90 and DSM-IV diagnoses provided by the Sleep-EVAL expert system were used for the comparisons.N/A.N/A.N/A.8% of the adolescents and 12.6% of the young adults had ICSD dyssomnia or sleep disturbances associated with a mental disorder. According to the DSM-IV classification, 5.7% of the adolescents and 8.1% of the young adults had a dyssomnia diagnosis. The comparison between the two classifications show that 73.2% of adolescents and young adults with a DSM-IV dyssomnia diagnosis also had similar ICSD diagnosis. The reverse comparison, ICSD vs. DSM-IV, shows that 39.8% of the subjects with an ICSD diagnosis had a DSM-IV diagnosis. DSM-IV primary insomnia was the most frequent diagnosis. Subjects with such a diagnosis were found in about 10 different ICSD diagnoses, mainly inadequate sleep hygiene, psychophysiological or idiopathic insomnia and insufficient sleep syndrome.ICSD-90 classification provided higher prevalence of sleep disorder diagnoses than the DSM-IV classification. In adolescents and young adults, DSM-IV primary insomnia is two times more often associated with ICSD inadequate sleep hygiene than with ICSD psychophysiological or idiopathic insomnia.

What are the contributing factors for insomnia in the general population?JOURNAL OF PSYCHOSOMATIC RESEARCHOhayon, M. M., Roth, T.2001; 51 (6): 745-755

Abstract

Lack of a systematic assessment of insomnia has led to large variations in its reported prevalence in the general population. This study aims to provide new guidelines to assess insomnia prevalence. A cross-sectional telephone survey using the Sleep-EVAL system was done with 24,600 general population-based subjects 15 years and older representative of general populations (France, the UK, Germany, Italy, Portugal, and Spain) consisting of 251,405,391 inhabitants. The overall participation rate was 81.0%. Within the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) symptomatology for insomnia, 27.2% (95% confidence interval: 26.6-27.8%) of the sample reported difficulty initiating sleep (DIS) (10.1%) or maintaining sleep (DMS) (disrupted sleep (DS): 18.0%; early morning awakening (EMA): 10.9%) or nonrestorative sleep (NRS) (8.9%) at least three times per week; 48.5% of them were concomitantly suffering of a DSM-IV sleep/mental disorder. A factor analysis identified several variables strongly related to each of the major factors of insomnia allowing: (1) The narrowing of the definition of insomnia: the prevalence of insomnia decreased to 16.8% with 64.5% of insomnia subjects having a DSM-IV sleep/mental disorder; (2) The identification of a sleep-deprived (voluntary or not) group without insomnia symptoms, representing 2.1% (1.9-2.3%) of the sample. Interestingly, the latter group closely matched the definition of insufficient sleep syndrome as described by the International Classification of Sleep Disorders (ICSD). Using more delineated criteria to assess insomnia increases the recognition of subjects complaining about sleep. Classifications should be amended to improve the correct identification of insomnia. Sleep-deprived subjects should also not be neglected.

Abstract

Global sleep dissatisfaction (GSD) is not part of the habitual insomnia symptoms in epidemiological studies. Furthermore, none of these studies has examined the relative importance of the various factors correlated to sleep dissatisfaction. This study aims to examine the links between GSD and insomnia and to find the factors contributing to GSD.A cross-sectional telephone survey was conducted in Germany (66 million inhabitants 15 years of age or older) with a representative sample of 4,115 subjects aged 15 years or older. Interviewers used the Sleep-EVAL system. The questionnaire covered several topics that were grouped into six classes of variables identified as potential factors associated with sleep dissatisfaction: sociodemographic descriptors, environmental factors, life habits, health status, psychological factors, sleep/wake factors.N/A.A representative sample of 4,115 subjects aged 15 years or olderN/A.Overall, 7% of the subjects reported being GSD; 95.5% of them had at least one insomnia symptom. The duration of insomnia symptom(s) was 20 months longer in GSD subjects compared to insomnia subjects without GSD. The prevalence of GSD was higher in women than in men and increased with age. The most significant predictive factors for GSD were: 1) for sleep/wake schedule variables: night sleep duration less than 6 hours (OR: 4.0 and over) and sleep latency greater than 30 minutes. 2) for sociodemographic variables: age between 65 and 74 (OR: 6.7) 3) for health variables: Upper airway disease (OR: 7.1); 4) for mental health variables: anxiety symptoms (OR: 3.0); 5) for environmental factors: too hot bedroom (OR=2.5) 6) for life habit factors: the need of a particular object in order to fall asleep (OR: 2.4).This study confirms that GSD is a better indicator of an underlying pathology than the classical insomnia symptoms alone: compared to insomniac subjects without GSD, subjects with GSD were two times more likely to report excessive daytime sleepiness, and eight times more likely to have a diagnosis of sleep or mental disorder. Furthermore, in car drivers, road accidents in the previous year were two times more frequent with GSD drivers as compared to insomnia drivers without GSD. Subjects with GSD were more than 10 times more likely to seek help for their sleep problems and five times more likely to use a sleep medication than insomnia subjects without GSD.

Abstract

From 1985 through 1995, 348 infants aged 3 wk-3 mo were referred to the Stanford Sleep Clinic for "apparent life-threatening events" (ALTE). A small group of 48 infants with no history of sleep-disordered breathing (SDB) was also recruited and used as controls (they comprised group C). We conducted a systematic investigation of relatives (parents, siblings, and grandparents) of the infants, including a clinical evaluation, craniofacial investigation, and the completion of an extensive (189-question) validated sleep/wake questionnaire. All data were calculated before the subdivision of ALTE infants into two groups. The subdivision was based on a blind scoring of the infants' polygraphic recordings; 42.5% of the infants were negative for SDB (Group A), whereas 57.5% of the infants were positive for SDB (Group B). Groups A and C were not significantly different from each other. Forty-three percent of the relatives of Group B infants had been treated for SDB (with nasal CPAP, surgical or dental appliance treatments) compared with 7.1% of Group A relatives. Clinical investigation indicated a significantly higher presence of small upper airways in the families of infants with SDB. About twice as many relatives reported the presence of asthma in Group B compared with Group A. Naso-oro-maxillomandibular anatomic traits that may lead to small upper airways in parents may be risk factors for abnormal breathing during sleep in their infants.

Abstract

This study has investigated differences in the nocturnal sleep and daytime sleepiness among patients with obstructive sleep apnoea syndrome (OSAS), upper airway resistance (UARS), sleep hypopnoea syndrome, and normal control subjects, using sleep scoring and spectral activity analysis of the electroencephalogram (EEG). Twelve nonobese males with UARS aged 30-60 yrs were recruited. These subjects were strictly matched for age and body mass index with twelve OSAS patients, 12 sleep hypopnoea syndrome patients, and 12 normal controls, all male. Daytime sleepiness was evaluated using the Epworth Sleepiness Scale (ESS) and the Multiple Sleep Latency Test (MSLT). The macrostructure of sleep was determined using international criteria and spectral analysis of the sleep EEG was obtained from a central lead. The sleep macrostructure of OSAS and UARS patients was significantly different from that of controls. These patients were also sleepier during the daytime than controls. Complaints of tiredness and daytime sleepiness, ESS and MSLT scores were similar in the different patient groups. Mild dysmorphia was present in all three patient groups. However, nocturnal sleep was significantly different among the different groups. OSAS patients had significantly more awake time during sleep than the UARS patients. The spectral activity of the total sleep time of the patient groups also differed significantly from that of controls. When the sleep spectral activity of UARS and OSAS patients were compared, OSAS patients had less slow wave sleep activity than UARS patients. UARS patients had a significantly higher absolute power in the 7-9 Hz bandwidth than OSAS patients. The absolute delta power over the different sleep cycles was also different between controls and patients, and between UARS and OSAS patients. There are clear differences in the macrostructure and spectral activity of sleep between upper airway resistance and obstructive sleep apnoea syndrome patients, demonstrated by differences in the cortical activity recorded in the central lead during sleep. Despite these nocturnal sleep differences, the tests of subjective daytime sleepiness are not significantly different.

How age and daytime activities are related to insomnia in the general population: Consequences for older peopleJOURNAL OF THE AMERICAN GERIATRICS SOCIETYOhayon, M. M., Zulley, J., Guilleminault, C., Smirne, S., Priest, R. G.2001; 49 (4): 360-366

Abstract

To determine the role of activity status and social life satisfaction on the report of insomnia symptoms and sleeping habits.Cross-sectional telephone survey using the Sleep-EVAL knowledge base system.Representative samples of three general populations (United Kingdom, Germany, and Italy).13,057 subjects age 15 and older: 4,972 in the United Kingdom, 4,115 in Germany, and 3,970 in Italy. These subjects were representative of 160 million inhabitants.Clinical questionnaire on insomnia and investigation of associated pathologies (psychiatric and neurological disorders).Insomnia symptoms were reported by more than one-third of the population age 65 and older. Multivariate models showed that age was not a predictive factor of insomnia symptoms when controlling for activity status and social life satisfaction. The level of activity and social interactions had no influence on napping, but age was found to have a significant positive effect on napping.These results indicate that the aging process per se is not responsible for the increase of insomnia often reported in older people. Instead, inactivity, dissatisfaction with social life, and the presence of organic diseases and mental disorders were the best predictors of insomnia, age being insignificant. Healthy older people (i.e., without organic or mental pathologies) have a prevalence of insomnia symptoms similar to that observed in younger people. Moreover, being active and satisfied with social life are protective factors against insomnia at any age.

Abstract

Sleep bruxism can have a significant effect on the patient's quality of life. It may also be associated with a number of disorders. However, little is known about the epidemiology of sleep bruxism and its risk factors in the general population.Cross-sectional telephone survey using the Sleep-EVAL knowledge based system.Representative samples of three general populations (United Kingdom, Germany, and Italy) consisting of 158 million inhabitants.Thirteen thousand fifty-seven subjects aged > or = 15 years (United Kingdom, 4,972 subjects; Germany, 4,115 subjects; and Italy, 3,970 subjects).None.Clinical questionnaire on bruxism (using the International Classification of Sleep Disorders [ICSD] minimal set of criteria) with an investigation of associated pathologies (ie, sleep, breathing disorders, and psychiatric and neurologic pathologies).Grinding of teeth during sleep occurring at least weekly was reported by 8.2% of the subjects, and significant consequences from teeth grinding during sleep (ie, muscular discomfort on awakening, disturbing tooth grinding, or necessity of dental work) were found in half of these subjects. Moreover, 4.4% of the population fulfilled the criteria of ICSD sleep bruxism diagnosis. Finally, subjects with obstructive sleep apnea syndrome (odds ratio [OR], 1.8), loud snorers (OR, 1.4), subjects with moderate daytime sleepiness (OR, 1.3), heavy alcohol drinkers (OR, 1.8), caffeine drinkers (OR, 1.4), smokers (OR, 1.3), subjects with a highly stressful life (OR, 1.3), and those with anxiety (OR, 1.3) are at higher risk of reporting sleep bruxism.Sleep bruxism is common in the general population and represents the third most frequent parasomnia. It has numerous consequences, which are not limited to dental or muscular problems. Among the associated risk factors, patients with anxiety and sleep-disordered breathing have a higher number of risk factors for sleep bruxism, and this must raise concerns about the future of these individuals. An educational effort to raise the awareness of dentists and physicians about this pathology is necessary.

Prevalence of hallucinations and their pathological associations in the general populationPSYCHIATRY RESEARCHOhayon, M. M.2000; 97 (2-3): 153-164

Abstract

Hallucinations are perceptual phenomena involved in many fields of pathology. Although clinically widely explored, studies in the general population of these phenomena are scant. This issue was investigated using representative samples of the non-institutionalized general population of the United Kingdom, Germany and Italy aged 15 years or over (N=13,057). These surveys were conducted by telephone and explored mental disorders and hallucinations (visual, auditory, olfactory, haptic and gustatory hallucinations, out-of-body experiences, hypnagogic and hypnopompic hallucinations). Overall, 38.7% of the sample reported hallucinatory experiences (19.6% less than once in a month; 6.4% monthly; 2.7% once a week; and 2.4% more than once a week). These hallucinations occurred, (1) At sleep onset (hypnagogic hallucinations 24.8%) and/or upon awakening (hypnopompic hallucinations 6.6%), without relationship to a specific pathology in more than half of the cases; frightening hallucinations were more often the expression of sleep or mental disorders such as narcolepsy, OSAS or anxiety disorders. (2) During the daytime and reported by 27% of the sample: visual (prevalence of 3.2%) and auditory (0.6%) hallucinations were strongly related to a psychotic pathology (respective OR of 6.6 and 5.1 with a conservative estimate of the lifetime prevalence of psychotic disorders in this sample of 0.5%); and to anxiety (respective OR of 5.0 and 9.1). Haptic hallucinations were reported by 3.1% with current use of drugs as the highest risk factor (OR=9.8). In conclusion, the prevalence of hallucinations in the general population is not negligible. Daytime visual and auditory hallucinations are associated with a greater risk of psychiatric disorders. The other daytime sensory hallucinations are more related to an organic or a toxic disorder.

Abstract

Despite many constraints on time schedules among teenagers, epidemiological data on sleep complaints in adolescence remain limited and are nonexistent for sleep disorders. This study provides additional data on sleep habits and DSM-IV sleep disorders in late adolescence.A representative sample of 1,125 adolescents aged 15 to 18 years was interviewed by telephone using the Sleep-EVAL system. These adolescents came from 4 European countries: France, Great Britain, Germany, and Italy. Information was collected about sociodemographic characteristics, sleep/wake schedule, sleep habits, and sleep disorders and was compared with information from 2,169 young adults (19-24 years of age).Compared with young adults, adolescents presented with a distinct sleep/wake schedule: they went to sleep earlier, they woke up later, and they slept longer than young adults did. On weekends and days off, they also slept more than young adults did. However, the prevalence rates of sleep symptoms and sleep disorders were comparable in both groups. Approximately 25% reported insomnia symptoms and approximately 4% had a DSM-IV insomnia disorder. Fewer than 0.5% had a circadian rhythm disorder.Prevalence of insomnia disorders is lower in the adolescent population than in middle-aged or elderly adults. However, a rate of 4% in this young population is important given their young age and the consequences for daytime functioning.

Abstract

The aim of the study was to assess sleep disturbances in subjects with posttraumatic stress disorder (PTSD) from an urban general population and to identify associated psychiatric disorders in these subjects. The study was performed with a representative sample of 1,832 respondents aged 15 to 90 years living in the Metropolitan Toronto area who were surveyed by telephone (participation rate, 72.8%). Interviewers used Sleep-EVAL, an expert system specifically designed to conduct epidemiologic studies of sleep and mental disorders in the general population. Overall, 11.6% of the sample reported having experienced a traumatic event, with no difference in the proportion of men and women. Approximately 2% (1.8%) of the entire sample were diagnosed by the system as having PTSD at the time of interview. The rate was higher for women (2.6%) than for men (0.9%), which translated into an odds ratio (OR) of 2.8 (95% confidence interval [CI], 1.3 to 6.1). PTSD was strongly associated with other mental disorders: 75.7% of respondents with PTSD received at least one other diagnosis. Most concurrent disorders (80.7%) appeared after exposure to the traumatic event. Sleep disturbances also affected about 70% of the PTSD subjects. Violent or injurious behaviors during sleep, sleep paralysis, sleep talking, and hypnagogic and hypnopompic hallucinations were more frequently reported in respondents with PTSD. Considering the relatively high prevalence of PTSD and its important comorbidity with other sleep and psychiatric disorders, an assessment of the history of traumatic events should be part of a clinician's routine inquiry in order to limit chronicity and maladjustment following a traumatic exposure. Moreover, complaints of rapid eye movement (REM)-related sleep symptoms could be an indication of an underlying problem stemming from PTSD.

Abstract

OBJECTIVES Sleep-disordered breathing has been hypothesized to have a close relationship with hypertension but previous studies have reported mixed results. This is an important health issue that requires further clarification because of the potential impact on the prevention and control of hypertension.The relationship between hypertension and three forms of sleep-disordered breathing (chronic snoring, breathing pauses and obstructive sleep apnea syndrome (OSAS)) was assessed using representative samples of the non-institutionalized population of the UK, Germany and Italy (159 million inhabitants). The samples were comprised of 13,057 individuals aged 15-100 years who were interviewed about their sleeping habits and their sleep symptoms over the telephone using the Sleep-EVAL system.OSAS was found in 1.9% (95% CI: 1.2% to 2.3%) of the UK sample, 1.8% (95% CI: 1.4% to 2.2%) of the German sample and 1.1% (95% CI: 0.8% to 1.4%) of the Italian sample. OSAS was an independent risk factor (odds ratio (OR): 9.7) for hypertension after controlling for possible confounding effects of age, gender, obesity, smoking, alcohol consumption, life stress, and, heart and renal disease.Results from three of the most populated countries in Western Europe indicate that OSAS is an independent risk factor for hypertension. Snoring and breathing pauses during sleep appeared to be non-significant predictive factors.

The place of confusional arousals in sleep and mental disorders - Findings in a general population sample of 13,057 subjectsJOURNAL OF NERVOUS AND MENTAL DISEASEOhayon, M. M., Priest, R. G., Zulley, J., Smirne, S.2000; 188 (6): 340-348

Abstract

Confusional arousals, or sleep drunkenness, occur upon awakening and remain unstudied in the general population. We selected a representative sample from the United Kingdom, Germany, and Italy (N = 13,057) and conducted telephone interviews. Confusional arousals were reported by 2.9% of the sample: 1% (95% confidence interval: .8 to 1.2%) of the sample also presented with memory deficits (53.9%), disorientation in time and/or space (71%), or slow mentation and speech (54.4%), and 1.9% (1.7% to 2.1%) reported confusional arousals without associated features. Younger subjects (< 35 years) and shift or night workers were at higher risk of reporting confusional arousals. These arousals were strongly associated with the presence of a mental disorder with odds ratios ranging from 2.4 to 13.5. Bipolar and anxiety disorders were the most frequently associated mental disorders. Furthermore, subjects with Obstructive Sleep Apnea Syndrome (OSAS), hypnagogic or hypnopompic hallucinations, violent or injurious behaviors, insomnia, and hypersomnia are more likely to suffer from confusional arousals. Confusional arousals appears to occur quite frequently in the general population, affecting mostly younger subjects regardless of their gender. Physicians should be aware of the frequent associations between confusional arousals, mental disorders, and OSAS. Furthermore, the high occurrence of confusional arousals in shift or night workers may increase the likelihood of inappropriate response by employees sleeping at work.

Abstract

To attempt, for the first time, to apply a positive and differential diagnosis process in the general population during interviews using DSM-IV classification to ascertain the profile and occurrence of concomitant mental disorders.A representative sample of 1832 individuals aged 15 years or older living in the metropolitan area of Toronto were interviewed by means of telephone interviews. The participation rate was 72.8%.Overall, 13.2% (n = 242) of the sample had either a mood disorder (n = 127; 6.9%) or an anxiety disorder (n = 170; 9.3%) at the time of their interview. The prevalence was higher among women (16.5%) than among men (9.7%), with an odds ratio of 1.8. The comorbidity of mood and anxiety disorders was found in 3% (n = 55) of the sample. Less than one-third of respondents with a mood and/or anxiety disorder were being treated by a physician for a mental disorder. However, these individuals were greater consumers of health care services. Most of them consulted a physician an average of 5 times in the past year. Individuals on medication diagnosed with a mood and an anxiety disorder consulted a physician an average of 12 times in the past year. Only 13% of them were treated with antidepressants and under 9% with anxiolytics.More than 70% of subjects with a mood disorder also complained of insomnia. With the differential process, 12% of the subjects manifesting a full-fledged anxiety disorder were diagnosed with only a mood disorder because the anxiety occurred only in the course of the mood disorder. About two-thirds of the subjects diagnosed in this study were undiagnosed and untreated by their physician.

Abstract

Objective: (i) Evaluation of the clinical differences and similarities presented by patients diagnosed as OSAS and UARS subjects. (ii) Evaluation of the ability of a sleep disorders specialist to dissociate the two syndromes based upon clinical evaluation.Population: 314 subjects were included. They were referred to a sleep disorders clinic with complaints of loud snoring during a 3 month period.Method: The evaluation consisted of: (i) Clinical interview and evaluation. (ii) Administration of validated questionnaires (Sleep Disorders Questionnaire and Epworth Sleepiness Scale). (iii) Establishment of clinical diagnostic and results of polygraphic recording.Results: After clinical evaluation and polygraphic recordings (performed within 3 weeks of initial evaluation) patients were subdivided into two groups: 176 OSAS and 128 UARS. The misclassification of patients by specialists correlated with body mass index (BMI) measurement, with an over classification of patient as OSAS when a high BMI was noted and vice-versa for UARS. The only significant difference between OSAS and UARS patients was an older age and a wider neck circumference in the OSAS group than in UARS patients.Conclusion: Clinical presentation including daytime sleepiness complaint and ESS score is similar for patients with and without drop of oxygen saturation below 90% during sleep. There was always a male predominance within both syndromes, but more women were diagnosed with UARS than with OSAS.

Abstract

To validate the Sleep-EVAL expert system, a computerized tool designed for the assessment of sleep disorders, against polysomnographic data and clinical assessments by sleep specialists.Patients were interviewed twice, once by a physician using Sleep-EVAL and again by a sleep specialist. Polysomnographic data were also recorded to ascertain diagnoses. Agreement between diagnoses generated by Sleep-EVAL and those formulated by sleep specialists was determined via the kappa statistic.Sleep disorder centers at Stanford University (USA) and Regensburg University (Germany).105 patients aged 18 years or over.NA.Sleep-EVAL made an average of 1.32 diagnoses per patient, compared with 0.93 for the sleep specialists. Overall agreement on any sleep-breathing disorder was 96.9% (Kappa .94). More than half of the patients were diagnosed with obstructive sleep apnea syndrome (OSAS); the agreement rate for this specific diagnosis was 96.7% (Kappa .93).The findings indicate that the Sleep-EVAL system is a valid instrument for the recognition of major sleep disorders, particularly insomnia and OSAS.

Abstract

Epidemiological studies can provide information not only on specific diagnostic entities but also on their underlying symptomatic constellations. For this purpose, an expert system was developed for the assessment of sleep disorders and endowed with the fuzzy logic capabilities necessary to determine the degree to which a given symptom corresponds to a specific diagnosis. Uncertainty is inherent in fields such as sleep medicine and psychiatry, and becomes evident in clinical practice at the stages of data collection and diagnostic formulation, when the clinician must determine whether a symptom is present and must choose from several diagnostic possibilities. The process involves a considerable degree of subjectivity on the part of the patient in trying to describe his or her symptoms, and of the clinician whose final diagnosis will depend on his or her clinical experience and interpretation of what is normal and what is pathological. Inferential models of the probabilistic or fuzzy logic type take into account such uncertainty. The Sleep-Eval system has been used in epidemiological and clinical studies involving 34,044 interviews collected by close to 300 interviewers. The diagnostic potential of these models is illustrated using data collected in an epidemiological study of the noninstitutionalized general population of Italy and underlines the advantages and limits of the binary, bayesian, and fuzzy logic methods and analyses.

Abstract

Although frequently investigated in the general population, the epidemiology of insomnia complaints and their treatment have received little attention in general practice. This study recruited patients > or =15 years of age, consecutively, from 127 general practitioners in France. The physicians collected data from 11,810 of their patients, of whom 55.5% were women. Insomnia complaints were reported by 26.2% (25.4% to 27%) of the sample and use of sleep-promoting medication by 10.1% (9.7% to 10.7%). About 47% of the prescribed drugs used were anxiolytics and 45% hypnotics. Most consumers took sleep-enhancing drugs on a daily and long-term basis and most reported that the medication improved their quality of sleep. However, few distinctions emerged between elderly drug-taking insomniacs and elderly nontreated insomniacs with respect to the various dimensions of sleep. Results underscore the persistent general tendency among French general practitioners to overprescribe anxiolytics for the treatment of insomnia complaints and that they do so on a long-term basis, despite the findings of numerous studies showing that benzodiazepines are ineffective in the treatment of sleep complaints over the long term.

Abstract

To evaluate the sleep hygiene and prevalence of sleep deprivation among a large sample of automobile drivers.From the 15th of June to the 4th of August 1996, with the help of the French highway patrol, we randomly stopped automobile drivers at the toll booths of Bordeaux and Biarritz. All subjects completed a validated questionnaire on sleep/wake habits during the year. After answering the questionnaire, subjects completed a graphic travel and sleep log of the three days preceding the interview.We randomly stopped 2196 automobile drivers. Ninety-one percent of the sample (mean age 43 +/- 13 years) agreed to participate in the survey.Fifty percent of the drivers decreased their total sleep time in the 24 hours before the interview compared with their regular self-reported sleep time. 12.5% presented a sleep debt > 180 minutes, and 2.7% presented a sleep debt > 300 minutes. Being young, commuting to work, driving long distances, starting the trip at night, being an "evening" person, being a long sleeper during the week, and sleeping in on the week-end were risk factors significantly associated with sleep debt.The results of the study highlight variables (long-distance driving, youth, sleep restriction) that are frequently associated with sleep-related accidents.

Abstract

Previous epidemiologic data on sleep paralysis (SP) came from small specific samples. The true prevalence and associated factors of SP in the general population remain unknown.A representative sample of the noninstitutionalized general population of Germany and Italy age > or =15 years (n = 8,085) was surveyed by telephone using the Sleep-EVAL questionnaire and the Sleep Questionnaire of Alertness and Wakefulness.Overall, 6.2% (5.7 to 6.7%) of the sample (n = 494) had experienced at least one SP episode in their lifetime. At the time of the interview, severe SP (at least one episode per week) occurred in 0.8% of the sample, moderate SP (at least one episode per month) in 1.4%, and mild SP (less than one episode per month) in 4.0%. Significant predictive variables of SP were anxiolytic medication, automatic behavior, bipolar disorders, physical disease, hypnopompic hallucinations, nonrestorative sleep, and nocturnal leg cramps.SP is less common in the general population than was previously reported. This study indicates that the disorder is often associated with a mental disorder. Users of anxiolytic medication were nearly five times as likely to report SP, even after we controlled for possible effects of mental and sleep disorders.

Abstract

The prevalence of major psychiatric disorders in the general population is difficult to pinpoint owing to widely divergent estimates yielded by studies employing different criteria, methods, and instruments. Depressive disorders, which represent a sizable mental health care expense for the public purse, are no exception to the rule.The prevalence of depressive disorders was assessed in a representative sample (n = 4972) of the U.K. general population in 1994. Interviews were performed over the telephone by lay interviewers using an expert system that tailored the questionnaire to each individual based on prior responses. Diagnoses and symptoms lists were based on the DSM-IV.Five percent (95% confidence interval = 4.4-5.6%) of the sample was diagnosed by the system with a depressive disorder at the time of the interview, with the rate slightly higher for women (5.9%) than men (4.2%). Unemployed, separated, divorced, and widowed individuals were found to be at higher risk for depression. Depressive subjects were seen almost exclusively by general practitioners (only 3.4% by psychiatrists). Only 12.5% of them consulted their physician seeking mental health treatment, and 15.9% reported being hospitalized in the past 12 months.The study indicates that mental health problems in the community are seriously underdetected by general practitioners, and that these professionals are highly reluctant to refer patients with depressive disorders to the appropriate specialist.

Abstract

To investigate the possible involvement of beta-amyloid (A beta) in disrupting neuronal function during ischemia, we examined whether overexpression of C-terminal fragments of beta-amyloid precursor protein (beta-APP) in transgenic (Tg) mice is capable of altering the capacity of hippocampus slices to recover synaptic transmission after transient hypoxic episodes. Recovery of synaptic transmission was monitored in area CA1 of perfused hippocampal slices prepared from both control and Tg mice. The results obtained indicate that hippocampal slices prepared from Tg mice exhibited a much lower level of recovery in synaptic transmission following reoxygenation. This reduction in the capacity of Tg slices to recover from hypoxia-induced impairment of synaptic transmission in the hippocampus does not appear to be related to pre-existing alterations in either functional or biochemical properties of glutamate receptors in Tg mice. The present results provide the first experimental evidence that overexpression of the C-terminal fragment of APP exacerbates functional damage of hippocampal neurons after hypoxic episodes.

Abstract

This paper summarizes the hypotheses accounting for the prevalence of mental disorder in prison. The hypotheses about the migration of prisoners, the criminalization of individuals with mental disorders, and the clinical specificity of subjects with mental disorders are introduced and discussed. A new hypothesis is proposed to account for the prevalence of mental disorder in prison, stating that the first instances of case management, either legal or medical, affect subsequent case management.The 4 aspects (political, administrative, individual, and cognitive) of the hypotheses enable the development of a multidimensional approach to account for the prevalence of mental disorder in prison.

Abstract

In adult rats, environmental enrichment has been shown to selectively increase -AMPA binding in the hippocampus but the molecular mechanisms underlying this effect remain unknown. We used in situ hybridization with antisense oligonucleotides to determine possible changes in the hippocampal expression of messenger RNAs for different subunits of AMPA receptors in adult rats following exposure to an enriched environment. Quantitative analysis revealed that mRNA levels for three subtypes of AMPA glutamate receptors (GluR1-3; Flip and Flop variants) were not modified in any hippocampal region after environmental enrichment. In addition, no differences were detected in the levels of GluR1 and GluR2/3 proteins in Western blots of hippocampal membranes from enriched rats. Nevertheless, quantitative ligand binding autoradiography indicated that environmental enrichment evoked a significant and uniform decrease in the capacity of calcium or phosphatidylserine (PS) to up-regulate -AMPA binding in various hippocampal regions but not in the cerebral cortex. These findings support previous observations suggesting that post-translational changes in AMPA receptor properties, as a result of the activation of calcium-dependent processes, may represent an important mechanism underlying long-term modifications of synaptic efficacy in the rat hippocampus.

Abstract

The co-occurrence of insomnia and mental disorders constitutes the most prevalent diagnosis pattern found in sleep disorder clinics. Yet, there remains a paucity of epidemiological information regarding comorbidity of mental disorders and sleep disorder symptomatology in the general population. The present study showed results based on a large representative French cohort (n = 5,622; 80.7% of the contacted stratified sample). A total of 997 (17.7%) individuals with insomnia complaints were identified and divided into six diagnostic categories: (1) Insomnia related to a Depressive Disorder; (2) Insomnia related to an Anxiety Disorder; (3) Depressive Disorder accompanied by insomnia symptomatology; (4) Anxiety Disorder accompanied by insomnia symptomatology; (5) Primary Insomnia; and (6) isolated insomnia symptomatology. Telephone interviews were conducted using the Sleep-Eval System. Subjects with insomnia related to a Mental Disorder have a longer history of insomnia complaints and are usually younger than those with Depressive or Anxiety Disorders accompanied by insomnia symptoms. Subjects with Insomnia related to a Depressive Disorder experienced more repercussions than any other group. A surprisingly high percentage of individuals with depressive symptomatology had sought independent medical treatment specifically for their sleep problems, which raises the unsettling possibility that many cases of depression go undetected by the general medical community. The distinct predictability of commonly undiagnosed depression leading to chronic depression speaks directly to the imperative that physicians receive additional training in this area of community mental health.

Abstract

To present current methods used to assess fitness to stand trial (FST), draw a parallel between these methods and studies of factors associated with decisions regarding FST, and describe the limits inherent to the field of FST.Survey of the relevant literature from Psychinfo and Medline databases from 1967 to 1996 inclusively.Ten instruments were identified for the systematic collection of information from persons assessed for FST. The description and analysis of their psychometric qualities, however, indicate that these instruments present some problems.Although some research has shown that diagnosis is the factor most associated with decisions regarding FST, no instrument includes a systematic assessment of psychopathology. If we take into account the possible consequences of these decisions for the accused as well as for society, these assessments and the recommendations that follow prove to be extremely important.

Abstract

To compare the characteristics of individuals assessed for fitness to stand trial (FST) with those assessed for criminal responsibility (CR).This study examines all the consecutive requests of FST or CR addressed to the only forensic psychiatric hospital in the province of Quebec and 2 prisons in the Montreal area over a 1-year period.In all, 170 FST, 52 CR, and 29 both FST and CR assessment requests were received (251 subjects). Psychiatrists' recommendations and court verdicts of unfitness to stand trial or not criminally responsible on account of mental disorders were mostly related to the presence of a psychotic-spectrum disorder. There is generally a good agreement between psychiatric recommendations and verdicts of the court, with the exception of unfitness recommendations.Defendants referred for a FST or a CR assessment displayed similar characteristics. However, although subjects with psychotic disorders represented more than one-half of the unfit or not criminally responsible verdicts, most of the subjects with psychoses were found competent to stand trial or responsible.

Abstract

The prevalence of psychotropic medication consumption was assessed in the UK by surveying a representative sample of 4972 non-institutionalized individuals 15 years of age or older (participation rate, 79.6%). A questionnaire was administered over the telephone with the help of the Sleep-Eval Expert System. Topics covered included: type and name of medication, indication, dosage, duration of intake, and medical specialty of prescriber. Also collected were data pertaining to sociodemographics, physical illnesses, and DSM-IV mental disorders. Overall, 3.5% [95% CI: 3-4] of the sample reported current use of psychotropic medication. Consumption was higher among women [4.6% (3.8-5.4)] than men [2.3% (1.7-2.9)], and among the elderly (> or = 65 years of age). The distribution of psychotropics was: hypnotics 1.5%, antidepressants 1.1%, and anxiolytics 0.8%. The median duration of psychotropic intake was 52 weeks. General practitioners were the most common prescribers of psychotropics (over 80% for each class of drug). Nearly half the antidepressant users were diagnosed by the system with a DSM-IV anxiety disorder, and one-fifth the anxiolytic users with a depressive disorder. A marked improvement in sleep quality was reported by half the subjects using a psychotropic for sleep-enhancing purposes. Psychotropic users were more likely than non-users to report episodes of memory loss, vertigo, or anomia. Psychotropic medication consumption is lower and patterns of psychotropic prescription differ in the UK compared with other European and North American countries. Results suggest that physicians may not be sufficiently trained to deal with the overlap between general practice and psychiatry.

Abstract

Sleep consists of two complex states--NREM and REM sleep--and disturbances of the boundaries between the states of sleep and wakefulness may result in violence. We investigated our population for reports of violence associated with sleep. REM behavior disorder is rarely associated with injury to the sufferer or others. NREM sleep related nocturnal wandering associated with self-inflicted injuries has variable etiologies. In the elderly, it is associated with dementia. In young individuals, it may be associated with mesio-temporal or mesio-frontal foci and an indication of a complex partial seizure. It also may be related to abnormal alertness and is associated with excessive daytime sleepiness, micro-sleeps, and hypnagogic hallucinations in sleep disorders such as narcolepsy or sleep disordered breathing.

Abstract

Daytime sleepiness is widespread and has negative impacts on the public sector.To ascertain the incidence and prevalence of daytime sleepiness and associated risk factors in the general population.In 1994, a representative sample of the non-institutionalized British population aged 15 years or older was interviewed via telephone using an expert computer-assisted program designed to facilitate surveys of this type (Sleep-Eval, M. M. Ohayon, Montreal, Quebec). Subjects were classified into 3 groups based on the severity of their daytime sleepiness. We completed 4972 interviews (acceptance rate, 79.6%).Severe daytime sleepiness was reported in 5.5% (95% confidence interval, 4.9%-6.1%) of the sample, and moderate daytime sleepiness in another 15.2% (95% confidence interval, 14.2%-16.2%). Associated factors with severe daytime sleepiness included female sex, middle age, napping, insomnia symptoms, high daily caffeine consumption, breathing pauses or leg pain in sleep, depressive disorder (based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria), falling asleep while reading or watching television, and motor vehicle crashes or accidents involving use of machinery. Moderate daytime sleepiness was associated with female sex, napping, insomnia symptoms, arthritis or heart disease, and gross motor movements during sleep.It is likely that daytime sleepiness deleteriously affects work activities, social and/or marital life, and exhibits a negative socioeconomic impact. In addition, the risk of a motor vehicle crash appears to be higher in this specific population: twice as many subjects operating a motor vehicle or using machine tools reported having a crash or accident, respectively, in the previous year in the groups with severe daytime sleepiness or moderate daytime sleepiness than did the general population with no daytime sleepiness. The high prevalence rates of daytime sleepiness and multiplicity of related factors mandate further scrutiny by public health officials.

Abstract

The complex nature of insomnia and its relationship with organic and mental disorders render diagnosis problematic for epidemiologists and physicians.A representative UK sample (non-institutionalised, > 14 years old) was interviewed by telephone (n = 4972; 79.6% participation rate) with the Sleep-EVAL system. Subjects fell into three groups according to presence of insomnia symptom(s) and/or sleep dissatisfaction.Insomnia symptoms occurred in 36.2% of subjects. Most of these (75.9%), however, reported no sleep dissatisfaction. In comparison, those also with sleep dissatisfaction had higher prevalence of sleep and mental disorders and longer duration of insomnia symptoms, and were more likely to take sleep-promoting medication, dread bedtime, and complain of light sleep, poor night-time sleep and daytime sleepiness.Insomnia sufferers differ as to whether they are satisfied or dissatisfied with sleep. Although insomnia symptoms are common in the general population, sleep disturbances among sleep-dissatisfied individuals are more severe. Sleep dissatisfaction seems a better indicator of sleep pathology than insomnia symptoms.

Abstract

Although the relative incidence of violent behavior during sleep (VBS) is presumed to be low, no epidemiologic data exist to evaluate the prevalence of the phenomenon or to begin to understand its precursors or subtypes. This study examined the frequency of violent or injurious behavior during sleep and associated psychiatric risk factors.A representative United Kingdom sample of 2078 men and 2894 women between the ages of 15 to 100 years (representing 79.6% of those contacted) participated in a telephone interview directed by the Sleep-EVAL expert system specially designed for conducting such diagnostic telephone surveys.Two percent (N = 106) of respondents reported currently experiencing VBS. The VBS group experienced more night terrors and daytime sleepiness than the non-VBS group. Sleep talking, bruxism, and hypnic jerks were more frequent within the VBS than the other group, as were hypnagogic hallucinations (especially the experience of being attacked), the incidence of smoking, and caffeine and bedtime alcohol intake. The VBS group also reported current features of anxiety and mood disorders significantly more frequently and reported being hospitalized more often during the previous 12 months than the non-VBS group. Subjects with mood or anxiety disorders that co-occurred with other nocturnal symptoms had a higher risk of reporting VBS than all other subjects.We have identified a number of sleep, mental disorder, and other general health factors that characterize those experiencing episodes of VBS. These findings suggest that specific factors, perhaps reflecting an interaction of lifestyle and hereditary contributions, may be responsible for the observed variability in this rare but potentially serious condition.

Abstract

Epidemiological studies of insomnia in the general population have reported high prevalence rates. However, few have applied diagnostic criteria from existing classification systems. Consequently. It is not possible to determine whether subjects suffered from a sleep disorder or whether the insomnia constituted a symptom of a mental disorder. Insomnia and its relationship with other mental disorders was investigated in the general population using DSM-IV criteria. A representative sample of 5622 subjects from the French population were interviewed about their sleep habits over the telephone by lay interviewers. The course and content of interviews were customized by means of the Sleep-Eval knowledge-based system. A total of 18.6% of the sample reported insomnia complaints. The presence of insomnia complaints, lasting for at least one month with daytime repercussions was found for 12.7% of the sample. Subsequently, subjects were classified according to the Sleep Disorder decision-making process proposed by the DSM-IV classification, but without the recourse of polysomnographic recordings. Specific sleep disorder diagnoses were given for 5.6% of the sample, mostly as insomnia related to another mental disorder, primary insomnia was given for 1.3% of the sample. Primary mental disorder diagnoses were supplied for 8.4% of the sample, mostly as generalized anxiety disorder. The results of this investigation emphasize the need to use classifications to determine whether subjects with insomnia complaints suffer from a sleep disorder or whether insomnia constitutes a symptom of some other mental disorder. These distinctions are of utmost importance as they have a bearing on the choice of treatment. Conversely, diagnoses were obtained by lay interviews, which may have caused a lack of recognition and/or discrimination for light or borderline symptomatology.

Abstract

To determine the prevalence of snoring, breathing pauses during sleep, and obstructive sleep apnoea syndrome and determine the relation between these events and sociodemographic variables, other health problems, driving accidents, and consumption of healthcare resources.Telephone interview survey directed by a previously validated computerised system (Sleep-Eval).United Kingdom.2894 women and 2078 men aged 15-100 years who formed a representative sample of the non-institutionalised population.Interview responses.Forty per cent of the population reported snoring regularly and 3.8% reported breathing pauses during sleep. Regular snoring was significantly associated with male sex, age 25 or more, obesity, daytime sleepiness or naps, night time awakenings, consuming large amounts of caffeine, and smoking. Breathing pauses during sleep were significantly associated with obstructive airways or thyroid disease, male sex, age 35-44 years, consumption of anxiety reducing drugs, complaints of non-restorative sleep, and consultation with a doctor in the past year. The two breathing symptoms were also significantly associated with drowsiness while driving. Based on minimal criteria of the International classification of Sleep Disorders (1990), 1.9% of the sample had obstructive sleep apnoea syndrome. In the 35-64 year age group 1.5% of women (95% confidence interval 0.8% to 2.2%) and 3.5% of men (2.4% to 4.6%) had obstructive sleep apnoea syndrome.Disordered breathing during sleep is widely underdiagnosed in the United Kingdom. The condition is linked to increased use of medical resources and a greater risk of daytime sleepiness, which augments the risk of accidents. Doctors should ask patients and bed partners regularly about snoring and breathing pauses during sleep.

How a general population perceives its sleep and how this relates to the complaint of insomniaSLEEPOhayon, M. M., Caulet, M., Guilleminault, C.1997; 20 (9): 715-723

Abstract

The traditional indicators of insomnia (i.e. difficulty initiating sleep, difficulty maintaining sleep, nonrestorative sleep, early morning awakening) were assessed in a representative sample of 1,722 French-speaking Montrealers (Canada) aged 15 to 100 years. These subjects were interviewed over the telephone (81.3% of contacted sample) by means of the Sleep-Eval software. Subjects were classified as either satisfied or dissatisfied with quality of sleep (SQS or DQS), with or without insomnia indicators (+I or -I). Sociodemographics, sleep-wake schedules, evening activities, medication intake, recent medical consultations, and social life were also investigated. DQS subjects composed 17.8% of the population (DQS + I: 11.2%; DQS - I: 6.5%), and 21.7% of subjects were classified as either DQS + I or SQS + I. Overall, 3.8% of subjects reported using a sleep-enhancing medication. Nonrestorative sleep did not significantly distinguish SQS and DQS subjects. The complaint of nonrestorative sleep is not a useful indicator of insomnia, despite its inclusion in all medical classifications. DQS - I and SQS + I subjects defy traditional classifications. A better understanding of sleep complaints and more accurate classifications will help physicians identify patients with insomnia and meet their needs more appropriately.

Abstract

1.Long-term consumption of hypnotics may lead to various side-effects, including impaired daytime and cognitive functioning and increased risk of accidents. Unfortunately, few guidelines exist for physicians to apply when attempting to withdraw hypnotics from patients. This study investigated whether withdrawal is facilitated by using zopiclone as a substitute drug and evaluated abrupt and gradual substitution techniques. 2.This open, multicentre and randomized study involved 1,002 male and female outpatients aged 18 years or over recruited by psychiatrists in Lyon, France. Patients had a mean age of 44 years, and 65.9% were women. Outpatients were chronic insomniacs being treated with a hypnotic for at least three weeks. The study included a substitution (D0-D35) and a withdrawal (D36-D56) stage. Patients were randomly drawn into three parallel groups: Group A underwent gradual substitution of zopiclone for the initial BZD; Group B was subjected to complete and immediate withdrawal of the initial BZD in favor of zopiclone; and Group C remained on the initial BZD, though told otherwise. The withdrawal stage began on D36 with a 50% reduction in medication and ended on D50 with complete withdrawal. 3.Groups A (gradual substitution) and B (abrupt substitution) presented a net improvement in sleep during the substitution stage. However, Group B displayed a better improvement in sleep-onset period, a decrease in nocturnal awakenings and an increased quantity of sleep. In the withdrawal stage, Groups A and B were similar but Group C displayed a deterioration in sleep. Following the withdrawal stage, 29% of patients in Group C, 18% in Group A and 19% in Group B resumed hypnotic use. 4.Discontinuation of this type of medication is possible in over three quarters of cases, provided that the prescribing physician adheres to a precise withdrawal protocol. Patients on zopiclone were less likely to resume consumption of hypnotics during the week of full withdrawal and were more satisfied with sleep than when treated with a BZD hypnotic. Finally, the results of the study showed that abrupt substitution yielded better results for chronic users of hypnotics.

Abstract

The comparability among epidemiological surveys of sleep disorders has been encumbered because of the array of methodologies used from study to study. The present international initiative addresses this limitation. Many such studies using the exact same methodology are being completed in six European countries (France, the United Kingdom, Germany, Italy, Portugal, and Spain), two Canadian cities (metropolitan areas of Montreal and Toronto), New York State, and the city of San Francisco. These surveys have been undertaken with the aim of documenting the prevalence of sleep disorders in the general population according to criteria of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) and the International Classification of Sleep Disorders (ICSD-90). Data are gathered over the telephone by lay interviewers using the Sleep-EVAL expert system. This paper describes the methodology involved in the realization of these studies. Sample design and selection procedures are discussed.

Abstract

A representative sample of 5,622 subjects between 15 and 96 years of age from the noninstitutionalized general population of France were interviewed by telephone concerning their sleeping habits and sleep disorders. The interviews were conducted using the Sleep-Eval knowledge-based system, a nonmonotonic, level 2 expert system with a causal reasoning mode. Questions investigated nightmares, based on the Diagnostic and Statistical Manual, fourth edition (DSM-IV), definition, psychopathological traits, and included 12 other groups of information, including sociodemographics, sleep-wake schedule, daytime functioning, psychiatric and medical history, and drug intake. The data from 1,049 subjects suffering from insomnia were considered for this analysis. Bivariate analyses, logistic regression analysis using the method of indicator contrasts for the investigation of independent variables, and calculation of significant odds ratios were performed. Nightmares were reported in 18.3% of the surveyed insomniac population and were two times higher in women than in men. The following factors were found to be significantly associated with nightmares 1) sleep with many awakenings, 2) abnormally long sleep onset, 3) daytime memory impairment following poor nocturnal sleep, 4) daytime anxiety following poor nocturnal sleep, and 5) being a woman. There was a strong association between the report of nightmares in women and the presence of either a depressive disorder, anxiety disorder, or both disorders together. When the effects of major psychiatric disorders were controlled for, nightmares were significantly associated with being a woman, feeling depressed after a poor night's sleep, and complaining of a long sleep latency. Nightmares can lead to a negative conditioning toward sleep and to chronic sleep complaints. Considering the frequency of nightmares in an adult insomniac population and the significant relationship between nightmares and certain subgroups, nightmares should receive more attention in patients, especially women complaining of disrupted sleep, as high rates of psychiatric disorders were found in this specific group.

Abstract

Preliminary data indicate that the use of a morphometric model, an expert system with standardized questions, and an evaluation of snoring can be effective tools for diagnosing upper-airway sleep-disordered breathing (UASDB) in many cases. This eliminates the need for many sleep recordings.

Abstract

The effects of phosphatidylserine (PS) on the binding properties of the AMPA (alpha-amino-3-hydroxy-5-methylisoxazolepropionic acid) and NMDA (N-methyl-D-aspartate) subtypes of glutamate receptors were analyzed by quantitative autoradiography of [3H]AMPA, [3H]6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and [3H]glutamate binding on rat brain tissue sections. Preincubation of brain sections with PS produced an increase in [3H]AMPA binding without modifying the binding properties of [3H]CNQX, an antagonist of AMPA receptors. This effect of PS appeared to be specific for the AMPA subtype of glutamate receptors as the same treatment did not modify [3H]glutamate binding to the NMDA receptors. Furthermore, the PS-induced increase in [3H]AMPA binding was different in various brain structures, being larger in the molecular layer of the cerebellum and almost absent in the striatum. Preincubation with calcium also augmented [3H]AMPA binding, and the lack of additivity of the effects of calcium and PS on [3H]AMPA binding strongly suggests that both treatments share a common mechanism(s) for producing increased agonist binding. Finally, the effect of PS on AMPA receptor properties was markedly reduced in rat brain sections prepared from neonatal rats at a developmental stage that is normally characterized by the absence of LTP expression in certain brain regions. The present data are consistent with the hypothesis that alteration in the lipid composition of synaptic membranes may be an important mechanism for regulating AMPA receptor properties, which could be involved in producing long-lasting changes in synaptic operation.

Abstract

Hypnagogic and hypnopompic hallucinations are common in narcolepsy. However, the prevalence of these phenomena in the general population is uncertain.A representative community sample of 4972 people in the UK, aged 15-100, was interviewed by telephone (79.6% of those contacted). Interviews were performed by lay interviewers using a computerised system that guided the interviewer through the interview process.Thirty-seven per cent of the sample reported experiencing hypnagogic hallucinations and 12.5% reported hypnopompic hallucinations. Both types of hallucinations were significantly more common among subjects with symptoms of insomnia, excessive daytime sleepiness or mental disorders. According to this study, the prevalence of narcolepsy in the UK is 0.04%.Hypnagogic and hypnopompic hallucinations were much more common than expected, with a prevalence that far exceeds that which can be explained by the association with narcolepsy. Hypnopompic hallucinations may be a better indicator of narcolepsy than hypnagogic hallucinations in subjects reporting excessive daytime sleepiness.

Abstract

The aging population in western countries and the increase in longevity make the problem of recognition and treatment of sleep disorders more acute in the elderly population. The risk of evolution of sleep disorders in the elderly leads to a greater weakness of their physical health, a greater dependence on their environment, and finally to more frequent recourse to institutionalization. We investigated sleep habits, sleep disorders and psychiatric diagnoses, physical illnesses and psychotropic drug consumption in a representative sample of the general population of France. Interviews were performed over the telephone by lay interviews using the Eval Knowledge Based System, a computerized system that guides the interviewer through the interview process, 6966 subjects were contacted, and 5622 interviews (80.8% of the potential sample) were completed. The sample was divided into four age groups: 15 to 44 years old (56.4%); 45 to 64 years old (25.6%); 65 to 74 years old (10.8%) and 75 years old or more (7.2%). Earlier bedtime, long sleep latency, spending more time in bed with a reduction of nocturnal sleep time, nocturnal awakenings and daytime naps were found more frequently in "young old" (65 to 75 years old) and "old old" subjects (75 years old or more). Daytime naps and spending more time in bed with a reduction of nocturnal sleep time also distinguished "old old" subjects from "young old" subjects. About half of "old old" subjects who complained about their sleep did not get a diagnosis of sleep disorder, nor psychiatric disorder (52.4%). An insomnia diagnosis was given in 14% of cases (mostly primary insomnia-6.7%) and a psychiatric diagnosis in 33.4% of cases (mostly anxiety diagnoses-28.2%). The rate of psychotropic drug consumption was 11.7% (95% Cl: 10.9% to 12.5%) for the entire sample. This consumption dramatically increased with age: 4.8% between 15 to 44 years old; 15.6% between 45 to 64 years old; 24.3% in "young old" subjects and 32.8% in "old old" subjects. Psychotropic drug consumption was distributed as follows: 6.4% of the sample used anxiolytic, 2.7% hypnotic, 1.5% antidepressant and 0.9% hypnotic and anxiolytic together. The chronic use (at least one year) of hypnotic or anxiolytic drugs was frequent in "old old" subjects (92.6% and 80.2%, respectively) and "young old" subjects (74% and 78% respectively). The assessment of sleep by the physician should be made part of the routine clinical examination of older subjects. Review of the etiology of insomnia complaints is crucial in the choice of treatment. The reflex of psychotropic prescription in case of poor sleep is neither sufficient nor desirable, especially because of the risk of chronic use of the prescription. These data underline the importance of educating physicians about consequences of long-term utilization of these drugs and on the need for sleep hygiene measures as alternative solutions for treating insomnia complaints.

Abstract

This study compared prescribed psychotropic medication patterns for reported sleep disorders in French and Quebec samples.The first study was undertaken in France (N = 5622) and the second in the metropolitan area of Montreal (N = 1722). Lay interviewers used a specialized knowledge-based system for the purpose of evaluating sleep disorders by telephone.Results showed similar prevalence of insomnia complaints in both samples (20.1% and 17.8%, respectively). A higher level of psychotropic consumption was found in France (11.7% [95% confidence interval (CI), 10.9 to 12.5]) compared with Quebec, however, where consumption was less than half the French rate (5.5% [95% CI, 4.4 to 6.6]). Both studies identified females and the elderly as the primary consumers of these drugs. For approximately two-thirds of both samples, sleep-promoting medications were prescribed for a year or longer, revealing a chronicity of the consumption. Approximately 4 out of 5 prescriptions for sleeping medications were ordered by general practitioners in both samples.These findings clearly show a higher prevalence of psychotropic drug use in the French compared with the Quebec population. The patterns of consumption and prescription, however, are quite similar in both studies.

Abstract

In the present study, we examined the KCl-induced increase in [3H] amino-3-hydroxy-5-methylisoxazole-4-propionate ([3H]AMPA) binding in telencephalic synaptoneurosomes and potentiation of synaptic transmission (KLTP) in hippocampal slices during development in rats. As previously reported, KCI-induced depolarization of telencephalic synaptoneurosomes resulted in a 40 +/- 5% increase in [3H]AMPA binding to membrane fractions in adult rats (3 months old). KCI-induced increase in [3H]AMPA binding was reduced to 24 +/- 5% and 15 +/- 5% at postnatal days (PND) 25-30 and PND 15-20 respectively, and was only 6 +/- 5% at PND 5-10. KLTP in area CA1 of hippocampus was most pronounced in adult slices (40 +/- 5%), and was reduced to 30 +/- 5% in slices prepared from PND 25-30 animals; KCI-induced LTP was absent in CA1 hippocampal slices prepared from PND 5-10 animals (3 +/- 5%). The decrease in KCI-induced changes in AMPA receptor binding in young animals was also associated with an altered capacity of the bee venom peptide, mellitin (a phospholipase A2 (PLA2) activator), to increase [3H]AMPA binding in synaptoneurosomes. The smaller effect of mellitin on [3H]AMPA binding in young animals was not due to a decreased ability of this peptide to release [3H]arachidonate from synaptoneuro-somes. The parallel modifications in the extent of depolarization-induced change in AMPA receptor binding and excitatory synaptic transmission during development further support the hypothesis that alterations in AMPA receptor properties may play a critical role in synaptic plasticity.

Abstract

The responsibility of psychotropic drugs as a cause of road traffic accidents remains difficult to evaluate with precision. Different studies performed in many countries provide a certain precision in relation to percentage of injured drivers whose blood contained psychotropic substances (8 to 10% according to studies). On the other hand, it is practically impossible to really know either these products were or were not the cause of the accidents because underlying or associated pathologies can equally create problems such as lack of attention and other vigilance deficits. There is also a possibility of suicidal or aggressive tendencies. A certain number of circadian and other chronobiological parameters also complicate the problem since the schedule (hour) as well as the day of the week or even the season can considerably modify vigilance and reaction time. Available medications able to create such problems are numerous and their mechanisms of action varied. They can influence vision, impulsiveness and vigilance. They can act either by direct mechanisms of sedation or, on the contrary, by raising inhibition through secondary mechanisms: delay in drug elimination or provoked insomnia. For the most part, incriminated medications belong to the different classes of sedative medicines: benzodiazepines, antiepileptics, some antihistaminic agents, some antidepressants, some thymo-regulators and some anti-hypertensives. Also included are desinhibitors or stimulant classes: amphetamines and related drugs, caffeine and codeine. Some of them can be used for their psychodysleptic properties: codeine and anticholinergic drugs. Finally, drug and medicinal associations can have unforeseen effects: for example, anticholinergics + alcohol + valpromide, etc. If it appears methodologically impossible that research could ever precisely quantify the share of responsibility of psychotropic drugs in causing road traffic accidents, this relation remains highly probable. It is therefore necessary that in the course of university and post-academic training, potential prescribers might regularly be advised of these risks. Lastly, public needs to be constantly informed.

Epidemiological study on insomnia in the general populationSLEEPOhayon, M.1996; 19 (3): S7-S15

Abstract

This study was conducted with a representative sample of the French population of 5,622 subjects of 15 years old or more. The telephone interviews were performed with EVAL, an expert system specialized for the evaluation of sleep disorders. From this sample, 20.1% of persons said that they were unsatisfied with their sleep or taking medication for sleeping difficulties or anxiety with sleeping difficulties (UQS). A low family income, being a woman, being over 65 years of age, being retired and being separated, divorced or widowed are significantly associated with the presence of UQS. A sleep onset period over 15 minutes, a short night's sleep and regular nighttime awakenings are also associated with UQS. Medical consultations during the past 6 months and physical illnesses are more frequent among the UQS group. The consumption of sleep-enhancing medication and medication to reduce anxiety is important: in the past, 16% of subjects had taken a sleep-enhancing medication and 16.2% a medication to reduce anxiety. At the time of the survey 9.9% of the population were using sleep-enhancing medication and 6.7% were using medication for anxiety. For most, hypnotic consumption was long-term: 81.6% had been using it for more than 6 months.

Abstract

1. During an epidemiological study conducted by telephone on sleep disorders in the metropolitan area of Montreal (Quebec, Canada), the authors found that 5% of subjects used psychotropic drugs. These drugs were usually prescribed by a general practitioner (72.9%). 2. From this population, the authors drew three groups of subjects: users with sleeping difficulties (USD); non users with sleeping difficulties (NUSD) and, non users without sleeping difficulties (NUWSD). 3. Results showed that the utilization of psychotropics was usually chronic and more frequent among the elderly and women. 4. In multivariate models, when users were compared to NUWSD, the authors found eight variables significantly associated with psychotropic consumption: age (> or = 55), sex (female), presence of physical illness, medical consultation, dissatisfaction with sleep onset period and sleep quantity, sleep onset period greater than 15 minutes, and to never or rarely dream. 5. When users were compared to NUSD, three variables were found to be associated with psychotropic consumption: age, to be formerly married, and to experience regular nighttime awakenings. 6. It appears that the utilization of psychotropic drugs does not increase the quality of sleep when consumers are compared to non treated insomniacs (NUSD) on parameters of sleep satisfaction.

Abstract

The problem of a medical expert system validation is generally complex. It requires a rigorous methodology of validation and must show proof of its practical competency in order to be used currently. Validation concerns the quality of conclusions provided by the system, the quality of the deductive process leading to these conclusions as well as the validity of its utilization. In this paper, some reflections, questions, and requirements are exposed that must be addressed to proceed to the validation of a knowledge base system in the field of medicine, especially the psychiatric field.

Abstract

Previous results have shown that chronic administration of the antidepressant trimipramine prevents the formation of long-term potentiation in the rat hippocampus. In the present study, we compared the effects of chronic administration of trimipramine on the binding properties of hippocampal glutamate receptors and on the modulation of the DL-alpha-amino-3-hydroxy-5- methyl-isoxazolpropionic acid (AMPA) receptors by phospholipase A2 (PLA2). Whereas the binding characteristics of various agonist and antagonist ligands to the N-methyl-D-aspartate and the AMPA receptors were not modified by trimipramine treatment, there was a significant reduction in the increase in 3H-AMPA binding elicited by PLA2 treatment. Since activation of PLA2 has been reported to play a critical role in the formation of long-term potentiation, possibly mediated through a modification of the AMPA receptors, the results strengthen the hypothesis that PLA2-induced modification of 3H-AMPA binding is an important component of synaptic plasticity.

Abstract

The high affinity binding of [3H]paroxetine was measured in rat cerebral cortex following chronic treatment (21 days) with imipramine (5 mg/kg), trimipramine (5 mg/kg) and fluoxetine (2 mg/kg), in adult (3-4 months) or neonatal (7 days of age) rats. Tissue concentrations of serotonin and of its metabolite 5-hydroxyindole-3-acetic acid were also determined by high-performance liquid chromatography in cingulate cerebral cortex, rostral neostriatum, hippocampus and midbrain raphe nucleus region. No differences were found in any of the parameters of [3H]paroxetine binding after antidepressant administration, in either adult or neonatal animals. In addition, endogenous serotonin and 5-hydroxyindole-3-acetic acid levels were not different from control values in any of the regions examined. The present study shows that the serotonin uptake recognition site is resilient to changes after chronic treatment with therapeutic doses of antidepressants, and emphasizes the potential usefulness of uptake site ligands as markers to quantify innervation densities within the brain.

Abstract

Are expert systems liable to be used as consultants in psychiatry? Most expert systems deal with an over-restricted part of psychiatry and cannot be a real help in everyday care. Moreover, most of them are not actually validated (the comparison between the system's and the expert's conclusions in a few cases is not enough). Another problem is that they reflect the uncertainties of nosographic problems. Validation of such systems needs the careful checking of the logical structure of the underlying nosography, the fitness of the structure's knowledge base and the fitness of the inference engine. Moreover, the naïve use of the system by untrained clinicians is the best means of validation since it provides real life proof of the ability of expert systems to make diagnoses in unselected cases where the need for a common diagnostic reference is clear (for example, epidemiologic, psychopharmacological ornosographic research). Some of the best known expert systems in the field of psychiatry are reviewed and another expert system, Adinfer, is presented. Developed since 1982, Adinfer is a forward-tracking level O system (in its simplified version for micro-computers). The knowledge base is a translation of the DSM-III-R into production rules. The program has been included in several software packages and used in many clinical studies, both among psychiatrists and physicians. The program has been validated with 1,141 unselected cases, and with 47 physicians: an 83% agreement rate was found between the system's and the physician's diagnoses, taking into account that the clinicians were asked to give their conclusions according to their usual nosography.(ABSTRACT TRUNCATED AT 250 WORDS)

Abstract

The effects of trimipramine (TRIM), an antidepressant agent, on both the induction and the maintenance of long-term potentiation (LTP) was investigated in area CA1 of hippocampal slice preparations. Chronic administration (7-9 days) of TRIM in rat caused a large reduction in the magnitude of LTP induced by a theta burst stimulation (TBS) paradigm. Results indicate that the reduction of LTP produced by trimipramine does not seem to result from major changes in the physiological properties of the slice preparations. First, paired-pulse facilitation was not impaired following the drug administration suggesting that transmitter release was not modified in TRIM-treated slices. Second, the burst responses evoked by high-frequency stimulation exhibited the typical buildup of depolarization, which is due to both a reduction of IPSPs and the activation of NMDA receptors. Finally, the treatment did not change the amount of short-term potentiation induced by TBS nor did it modify the component of excitatory postsynaptic potentials (EPSPs) mediated by the activation of NMDA receptors, suggesting that the NMDA receptor functions remained intact in TRIM-treated slices. Taken together the present data suggest that the loss of LTP maintenance in TRIM-treated animals is more likely the result of the disruption by trimipramine of cellular processes that follow LTP induction. In addition, the results provide evidence for a possible correlation between the reduction in LTP expression and learning deficits produced by chronic administration of trimipramine.

[Use of the Adinfer diagnostic system in a study of somatic disorders in general practice].Canadian journal of psychiatry. Revue canadienne de psychiatrieOhayon, M., Caulet, M., Bosc, M.1992; 37 (4): 213-220

Abstract

Somatic complaints are very common in general medical practice. They are not identified as psychic disorders and are treated symptomatically. We explore two kind of problems: 1. methodological problems such as the instruments to use to examine somatic complaints (it is evident that a checklist does not give the best results with suggestible patients); and 2. the relationships between somatic complaints and psychic disorders such as anxiety, depression and somatoform disorders. Psychiatric nosology is by no means clear and includes many diagnoses from "hysteria" to "hypochondria" or "psychosomatic", "somatization". In this study, we compare the symptoms collected by general practitioners, and their clinical diagnoses to those obtained by an automatic DSM-III diagnostic program. Adinfer was modified so that three DSM decision trees were systematically scanned: depressive, anxiety and somatoform disorders. This allows for an epidemiological study of somatic complaints and their relationship to depression and anxiety. The subjects' score on rating scales for anxiety and depression are compared with the diagnoses made by the expert system. We discuss the significance of somatic symptoms, the DSM classes and the value of expert systems in epidemiological studies.

Computers and artificial intelligence in psychiatry brief history and state of the artProceedings of the Annual Conference on Engineering in Medicine and BiologyRialle V, Ohayon M1991; 13 (3): 1280-1281

Abstract

It is clear that computers are but a poor brain models: the nervous system has many "processors" (neurons) in parallel, whereas von Neuman's machines work sequentially on a single processor. In complex systems, emergent properties cannot be inferred from the behaviour of single elements. Anthills display collective "meaningful" moves, while each ant seems to obey local interactions only. Likewise, large parallel networks of processing elements elicit emergent properties. Like brains, some of them are self-organizing systems. In large parallel processing networks, each unit performs an elementary computation: adding inputs from other units. Large nets display surprising spontaneous computational abilities: associative memories, classes, generalizations may be seen as emergent properties of the network. Symbols are dynamical entities, whose handing is driven by local interactions of activation/inhibition of related representations. In such models, representations (memories) are distributed in the whole network, as stable configurations. Indeed, the basic properties of representation in connectionist models seem closer to human mental objects than the classic Artificial Intelligence concepts. Connectionist models have been used in many fields, namely simulations of real neural networks, pattern recognition and artificial vision, speech recognition, language understanding and knowledge representation, problem solving... Connectionist models have been thus used in neurobiology as well as cognition. One basic structure seems indeed able to account for a range of cognitive functions, from perception to problem solving and high level cognitive tasks. Nevertheless studies about "pathological" networks are yet rare, still an open field... We explore some of these fields.

Abstract

The disturbances of cognitive processes in psychotic patients are well known: the delusional interpretation is "the inference from a right perception into a wrong concept" (Dromard), "an wrong intuition about the meaning of what is perceived, seen or heard" (H. Ey). Analogy is the very core of any cognitive process: relating a strange thing to some object already part of the experience enables to set up differences, oppositions, connections, classes. Any semantic process (something stands for another thing) originates in analogy. It is the basis of every interpretation and world's knowledge. Its soundness is by no means reliable, but for the inner strength of the analogical network and its power to integrate new objects. It's easy to fall out of the track... A wrong analogy, better, a wrong one that would not be acknowledged as a mistake, would be enough: the gap is quite narrow between interpretations leading either to understanding or to misreading, only filled through the relation of other people providing the necessary clues. The contemporary papers about cognitive process are driving towards two main trends: 1) Neuromimetic models, and the building of neuronal networks, whose emergent properties point out the basically analogical character of representations, learning and memory. 2) Cognitive models, dealing with representations and algorithms, and leading to Artificial Intelligence Programs. We tried to build a model (both cognitive and AI) of the analogical process and its psychotic disturbances. Our model describes how simple analogical problems are solved: If (A) becomes (B), what about (C)? Making up the psychological model and its AI translation led to propound the concept of Universes as sets consisting of ONE likely or relevant link between two objects, and such intrinsic of extrinsic properties of the objects as are involved in this relation. The model uses 3 different universes: Universe U1, made up of one of the possible transformation kinks from (A) to (B) and (A)'s properties involved in this actual transformation. Universe U2, made out of the likeness link between Universe U1 and (C). Universe U3, performing in fact the validation procedure of the result. The analogical reasoning goes through the three universes, along an iterative loop again and again until a nice result is found.(ABSTRACT TRUNCATED AT 400 WORDS)

Abstract

Animals have always occupied a privileged place beside man and with him form a couple, a duality. In the first part the authors study the psychology of the adopted animal. Then they look at greater length into the personality of his owner, with particular insistence on the reasons for acquiring it, on the choice of animal (dog, cat, horses), on the part it plays in the life of its master, and on the latter's reaction at his companion's death. They also tackle the problem of man's abnormal behaviour in relation to animals, especially bestiality.